An artist makes a hanging sculpture out of rhombus-shaped pieces. Each rhombus shape has diagonals of 3.5 centimeters and 5 centimeters. What is the area of each rhombus? 4.25 cm2 8.5 cm2 8.75 cm2 17.5 cm2
The area of each rhombus is 8.75 [tex]cm^2[/tex]. The correct option is 8.75 [tex]cm^2.[/tex]
To find the area of each rhombus, we can use the formula for the area of a rhombus:
Area = (diagonal1 × diagonal2) / 2
Given that the diagonals of the rhombus-shaped pieces are 3.5 centimeters and 5 centimeters, we can substitute these values into the formula:
Area = (3.5 cm × 5 cm) / 2
Area = 17.5 [tex]cm^2[/tex] / 2
Area = 8.75 [tex]cm^2[/tex]
Therefore, the area of each rhombus is 8.75 [tex]cm^2[/tex]. The correct option is 8.75 [tex]cm^2.[/tex]
for such more question on area
https://brainly.com/question/15822332
#SPJ8
Change these fractions into decimals. Do not round your answers:
a. 3 8
b. 1 9
Step-by-step explanation:
3/8 = 0.375
1/9 = 0.1111111111
Answer:
Step-by-step explanation:
I need help graphing this!! I cent do my table right please help ASAP!
y= 2(1/3^x)-2
Answer: Your line should start at (-1,6) then it should cross (0,0) so, straight down and a small curve. Then you should be at (0 -2), continue the small curve you made. DO not make it a parabola. it is basically just a straight line down, then a really long curve. Make sure you make the curve go across the entire graph.
i need the whole problem done and i don’t understand, i need a step by step to show my work. its at 12. PLS HELP
The surface area of given triangular prism = 24 ft².
For the given triangular prism
Base = 2 ft
height = 3 ft
side = 3ft
We know that,
Surface area of triangular prism
= side x base + 3x base x height
= 3 x 2 + 3x2x3
= 6 + 18
= 24 ft²
Thus,
Surface area = 24 ft²
To learn more about prism visit:
https://brainly.com/question/2918181
#SPJ1
What is the equation for this line?
y=2/3x-4 is the equation of the line where 2/3 is the slope.
We have to find the equation of line which is passing through points (0, -4) and (3, -2).
The slope intercept form of a line is y=mx+b, where m is slope and b is the y intercept.
The slope of line passing through two points (x₁, y₁) and (x₂, y₂) is
m=y₂-y₁/x₂-x₁.
Slope = -2+4/3-0
=2/3
Now let us find the y intercept.
-4=2/3(0)+b
b=-4
The equation of line is y=2/3x-4.
To learn more on slope of line click:
https://brainly.com/question/16180119
#SPJ1
50 Points! Multiple choice algebra question. Photo attached. Thank you!
Answer: D
Step-by-step explanation: -135
Need some help on this question!!!!!
The greater number of packages that can fit in the truck is 24000.
The volume of the part of the truck that is being filled is 375 cubic feet.
We have,
To determine the greater number of packages that can fit in the truck, we need to calculate the volume of both the packages and the part of the truck that is being filled.
The volume of a cube-shaped package:
The side length of the cube-shaped package is 1/4 feet.
The volume of a cube is given by V = s³, where s is the side length.
Therefore, the volume of each package is (1/4)³ = 1/64 cubic feet.
The volume of the part of the truck being filled:
The dimensions of the rectangular prism-shaped part of the truck are:
Length = 8 feet
Width = 6(1/4) feet = 6.25 feet
Height = 7(1/2) feet = 7.5 feet
The volume of a rectangular prism is given by V = length × width × height.
Therefore, the volume of the part of the truck being filled is:
8 × 6.25 × 7.5
= 375 cubic feet.
To calculate the greater number of packages that can fit in the truck, we divide the volume of the part of the truck by the volume of each package:
= 375 cubic feet / (1/64 cubic feet)
= 375 × 64
= 24000 packages.
Therefore,
The greater number of packages that can fit in the truck is 24000.
The volume of the part of the truck that is being filled is 375 cubic feet.
Learn more about prism here:
https://brainly.com/question/12649592
#SPJ1
A health store sells two different sized square granola bars. the side length of the smaller granola bar, C(x), is modeled by the function C(x)=1/4 square root x +2, where x is the area of the larger granola bar in square inches. which graph shows C(x)
The graph that best represents these characteristics is the one that shows an increasing curve with a flattened slope and is shifted upward. Option C
The function C(x) = (1/4)√x + 2 represents the side length of the smaller granola bar, where x is the area of the larger granola bar in square inches. To determine which graph shows C(x), we need to analyze the characteristics of the function.
First, let's consider the behavior of the function C(x) = (1/4)√x + 2:
Square Root Function: The term √x indicates that the function involves the square root of x. This means that as x increases, C(x) will also increase, but at a decreasing rate.
Scaling Factor: The coefficient (1/4) scales the square root of x. It affects the steepness of the function and causes C(x) to increase more slowly compared to a simple square root function.
Vertical Shift: The constant term (+2) shifts the entire function vertically upward by 2 units. This means that the graph will be raised by 2 units compared to a standard square root function.
Based on these characteristics, we can conclude that the graph of C(x) will be an increasing curve with a flattened slope compared to a simple square root function, and it will be shifted upward by 2 units.
Among the answer choices, the graph that best represents these characteristics is the one that shows an increasing curve with a flattened slope and is shifted upward. Without the actual graphs provided, it is difficult to specify the exact choice, but it should exhibit these features described above.
It is essential to refer to the available graphs or visually analyze the functions to determine the correct graph that shows C(x). Option C is correct.
For more question on graph visit:
https://brainly.com/question/19040584
#SPJ8
For triangle XYZ, m∠X = (2g + 16)° and the exterior angle to ∠X measures (4g + 38)°. Find the measure of ∠X and its exterior angle.
The angles in the triangle are as follows:
∠X = 58°
Exterior angle of ∠X = 122°
How to find the angle of a triangle?The sum of angles in a triangle is 180 degrees. The sum of the exterior angle and the interior angle of a triangle is 180 degrees.
Therefore, let's find the measure of ∠X in the triangle XYZ.
Hence,
m∠X = (2g + 16)°
The exterior angle of m∠X measures 4g + 38 degrees.
Hence,
2g + 16 + 4g + 38 = 180
6g + 54 = 180
6g = 180 - 54
6g = 126
g = 126 / 6
g = 21
Therefore,
∠X = (2(21) + 16)° = 42 + 16 = 58 degrees
Exterior angle of ∠X = 4(21) + 38 = 84 + 38 = 122
learn more on triangle here:https://brainly.com/question/29370232
#SPJ1
(-20,13) (16,15)
Can some find the slop for this question
Write the equation of the line, in slope-intercept form, with the
following information:
rate of change: undefined
point: (-3,2)
y = -3x + 2 is the equation of the line, in slope-intercept form, with the following information.
Thus, The most "popular" type of a straight line is one with a slope-intercept. Due of its simplicity, this is helpful to a lot of kids.
The slope and y-intercept of the straight line can be easily determined or read off from this form, making it possible to describe its properties without having access to the graph.
You may learn how to determine the equation of a line from any two points that this line passes through using the slope intercept form calculator.
Continue reading to find out what a linear equation's slope intercept form is, how to calculate a line's equation, and the significance of the slope intercept form equation in practical applications.
Thus, y = -3x + 2 is the equation of the line, in slope-intercept form, with the following information.
Learn more about straight line, refer to the link:
https://brainly.com/question/31693341
#SPJ1
In quantitative literacy
In quantitative literacy, the solution involves finding the LCM of the numbers and then squaring it to obtain the smallest square number that satisfies the given conditions.
In quantitative literacy, finding the smallest square number that is divisible by 8, 12, 15, and 20.
To solve the problem, we need to determine the least common multiple (LCM) of these four numbers.
Let's list the multiples of each number until we find a common multiple:
Multiples of 8: 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112, 120, ...
Multiples of 12: 12, 24, 36, 48, 60, 72, 84, 96, 108, 120, ...
Multiples of 15: 15, 30, 45, 60, 75, 90, 105, 120, ...
Multiples of 20: 20, 40, 60, 80, 100, 120, ...
From the lists above, we can see that 120 is the smallest common multiple of all the numbers. To find the smallest square number, we need to square 120:
120^2 = 14,400
The smallest square number that is divisible by 8, 12, 15, and 20 is 14,400.
In quantitative literacy, the solution involves finding the LCM of the numbers and then squaring it to obtain the smallest square number that satisfies the given conditions.
For more such questions on quantitative literacy
https://brainly.com/question/24692448
#SPJ8
Un atleta parte desde el reposo en una competencia al cabo de 30 segundos su velocidad es de 2m/s ¿cuál es la aceleración del atleta?
The required acceleration is 0.0666 [tex]m^{2}[/tex]/s.
Given that the velocity of the object is 2m/s and time is 30s.
Acceleration is the rate of change of velocity with respect to time.
To find the acceleration by using the formula.
acceleration (a) = velocity (v) / time (t).
By using data and formula gives,
acceleration (a) = velocity (v) / time (t).
acceleration (a) = 2 / 30
acceleration (a) = 0.0666 [tex]m^{2}[/tex]/s.
Hence, the required acceleration is 0.0666 [tex]m^{2}[/tex]/s.
Learn more about acceleration click here:
https://brainly.com/question/23541495
#SPJ1
What is the meaning of "we call a class R an n-ary relation if all its elements are n-tuples"?
The statement is saying that a class R is considered an n-ary relation if all its elements are n-tuples.
The symbol R⊂Vⁿ represents that the class R is a subset of Vⁿ, which is the class of all n-tuples.
Here, Vⁿ represents the set of all possible n-tuples, and R is a subset of that set.
The notation Cⁿ is used to denote the set of n-tuples with elements from the set C, and C×D represents the Cartesian product of sets C and D.
The statement defines an n-ary relation as a class where all its elements are n-tuples, and it establishes a connection between the class R and the set of all n-tuples (Vⁿ).
The notation Cⁿ and C×D are used to describe sets of n-tuples and Cartesian products, respectively, in a mathematical context.
To learn more on Cartesian product click:
https://brainly.com/question/30340096
#SPJ1
Find the probability of not rolling factors of 5 on both dice
The probability of not rolling factors of 5 on both dice is 25/36
Calculating the probability of not rolling factors of 5 on both diceFrom the question, we have the following parameters that can be used in our computation:
Rolling two number cubes
Using the above as a guide, we have the following:
Sample space, S = {1, 2, 3, 4, 5, 6}
In the above sample space, we have
Not factors of 5 = {1, 2, 3, 4, 6}
So, we have
P(Not rolling factor of 5) = 5/6 * 5/6
Evaluate
P(Not rolling factor of 5) = 25/36
Hence, the probability is 25/36
Read more about probability at
brainly.com/question/24756209
#SPJ1
Question
Two six sided dice are rolled.
Find the probability of not rolling factors of 5 on both dice
help please show work
The slope of line AD will be 4/3
Given,
ABCD is a square.
AB ⇒ y = -3/4 x + 7
Now,
AB is straight line.
Straight line equation ⇒ y =mx + c
m = slope of line
c = y intercept
Here,
m = -3/4 ( slope of line AB )
Now for slope of line AD,
ABCD is a square. Thus AB and AD are perpendicular to each other.
According the relation,
[tex]m_{1} m_{2} = -1[/tex]
[tex]m_{1}[/tex] = slope of line 1
[tex]m_{2}[/tex] = slope of line 2
So,
-3/4 [tex]m_{2}[/tex] = -1
[tex]m_{2}[/tex] = 4/3.
Hence slope of AD is 4/3 .
Know more about perpendicular lines,
https://brainly.com/question/9379960
#SPJ1
A set of twins purchase a small, oddly shaped plot of land for their retirement. They want to divide the parcel along the grid lines into two identical plots. Can they do it and how?
The ability of the twins to divide the oddly shaped plot into two Identical plots along the grid lines depends on the presence of a line of symmetry.
To determine whether the set of twins can divide the oddly shaped plot of land into two identical plots along the grid lines, we need to consider the characteristics of the plot and the conditions required for the division.
For the division to be possible, the plot needs to have a line of symmetry that can be used to create two identical halves. A line of symmetry divides an object into two equal and mirrored parts.
If the plot of land has a line of symmetry, the twins can divide it by drawing a line along the symmetry axis. This line should cut the plot into two equal halves, ensuring that both plots are identical.
However, if the plot does not have a line of symmetry, it may not be possible to divide it into two identical plots along the grid lines. In this case, the twins would need to consider alternative methods of division or compromise on the goal of having two identical plots.
To determine if the plot has a line of symmetry, the twins can examine its shape and characteristics. They can look for any symmetrical patterns, such as equal sides or mirrored shapes, that indicate the presence of a line of symmetry.
If the plot does not have an obvious line of symmetry, the twins might need to explore other options, such as dividing the plot into two equal areas based on other criteria, such as the length or width of each half.
the ability of the twins to divide the oddly shaped plot into two identical plots along the grid lines depends on the presence of a line of symmetry. If such a line exists, they can divide the plot by drawing a line along the symmetry axis. However, if the plot lacks symmetry, they may need to consider alternative methods of division or adjust their expectations.
To know more about Identical .
https://brainly.com/question/31354059
#SPJ8
Note the full question may be :
To determine whether the twins can divide the oddly shaped plot of land into two identical plots along the grid lines, we need more specific information about the shape and dimensions of the plot. the shape of the plot (rectangular, triangular, irregular), the lengths of its sides, any existing grid lines or divisions within the plot.
What is the rate of change for f(x) = 7 sin x-1 on the interval from x = 0 to x = pi/2
A)14/pi
B)pi/14
C)pi/4
D)4/pi
Answer:
a]14/pi
Step-by-step explanation:
P(-1; -1) S(-3; -7) Q(4; 2) R(7; -5) Determine (correct to one decimal place): 3.2 3.1 the acute angle between QR and the x-axis the angle of inclination of PQ POR 3.3 3.4 the angle of inclination of SP 3.5 SPR 3.6 PSR.
The support beams of truss bridges are triangles. James made a model of a truss bridge with a scale of 1 inch = 4 feet. If the height of the tallest triangle on the model is 9 inches, what is the height of the tallest triangle on the actual bridge?
The height of the tallest triangle on the actual bridge is 12 feet.
If James made a model of a truss bridge with a scale of 1 inch = 4 feet, we can use this information to find the height of the tallest triangle on the actual bridge.
Let x be the height of the tallest triangle on the actual bridge. Since the scale of the model is 1 inch = 4 feet, the height of the tallest triangle on the model can be converted to feet by multiplying by 4. Therefore, the height of the tallest triangle on the model is:
9 inches * (1 foot / 12 inches) * 4 = 3 feet
We can use the similarity of triangles to set up a proportion to find x. The corresponding sides of similar triangles are proportional. In this case, the height of the triangle on the model corresponds to the height of the triangle on the actual bridge, and the scale factor from the model to the actual bridge is 1/4 (since 1 inch on the model represents 4 feet on the actual bridge). Therefore, we have:
height of triangle on model / height of triangle on actual bridge = scale factor
3 feet / x = 1/4
Multiplying both sides by x, we have:
3 feet = (1/4) x
Multiplying both sides by 4, we have:
12 feet = x
For such more questions on height
https://brainly.com/question/73194
#SPJ8
(3a - 5b)(, + 5b)(a ^ 2 + ab - b ^ 2)
The solution after resolving into factors are,
⇒ 8 (a - 3b) (a - b)
We have to given that,
Resolve into factors the expression,
⇒ (3a - 5b)² - (a + b)²
Now, We can simplify for resolving the factors as,
⇒ (3a - 5b)² - (a + b)²
Since, WE know that,
⇒ x² - y² = (x - y) (x + y)
Hence,
⇒ (3a - 5b)² - (a + b)²
⇒ [(3a - 5b) - (a + b)] [ (3a - 5b) + (a + b)]
⇒ [3a - 5b - a - b] [4a - 4b]
⇒ (2a - 6b) (4a - 4b)
⇒ 2 (a - 3b) × 4 (a - b)
⇒ 8 (a - 3b) (a - b)
Thus, The solution after resolving into factors are,
⇒ 8 (a - 3b) (a - b)
Learn more about the mathematical expression visit:
brainly.com/question/1859113
#SPJ1
Find the equation using the point slope formula or slope intercept formula for the two sets of points. (19,-16) (-7,-15)
The equation of the Line passing through the points (19, -16) and (-7, -15) is: y = (-1/26)x - 397/26
The equation of a line using the point-slope formula or the slope-intercept form, we need either the slope of the line or the y-intercept. Let's calculate the slope of the line using the given points (19, -16) and (-7, -15).
The slope (m) can be calculated using the formula:
m = (y2 - y1) / (x2 - x1)
Using the coordinates (19, -16) as (x1, y1) and (-7, -15) as (x2, y2), we can substitute these values into the slope formula:
m = (-15 - (-16)) / (-7 - 19)
m = (-15 + 16) / (-7 - 19)
m = 1 / (-26)
m = -1/26
Now that we have the slope of the line, we can use either the point-slope formula or the slope-intercept form to find the equation.
Using the slope-intercept form, which is y = mx + b, where m represents the slope and b represents the y-intercept, we can substitute the slope (-1/26) and one of the given points (19, -16) into the equation:
-16 = (-1/26) * 19 + b
To solve for b, we can simplify the equation:
-16 = -19/26 + b
To isolate b, we can add 19/26 to both sides of the equation:
-16 + 19/26 = b
Now, we can find the common denominator of 26 and add the fractions:
(-416 + 19) / 26 = b
-397/26 = b
Therefore, the equation of the line passing through the points (19, -16) and (-7, -15) is: y = (-1/26)x - 397/26
This equation represents the line with a slope of -1/26 and a y-intercept of -397/26.
To know more about Line .
https://brainly.com/question/28732353
#SPJ8
A rectangular room is tiled with tiles 1
2
inches long and 1
2
inches wide. If the room is L tiles long and W tiles
wide, find the room’s area, in square inches.
The room’s area, in square inches is,
⇒ A = 144LW square inches.
We have to given that,
A rectangular room is tiled with tiles 12 inches long and 12 inches wide.
And, The room is L tiles long and W tiles wide.
Hence, Lenght of L tiles,
= 12L
And, Length of W tiles,
= 12W
Since, We know that,
Area of rectangle is,
⇒ A = Length x width
Substitute given values, we get;
⇒ A = 12L x 12W
⇒ A = 144LW square inches.
Therefore, The room’s area, in square inches is,
⇒ A = 144LW square inches.
Learn more about the rectangle visit:
https://brainly.com/question/2607596
#SPJ1
The following number is a BASE-7 NUMBER. Convert this to a base 10 number and enter your answer in the box.
463421
(Remember, the above number is in Base 7!)
Number in base 10:
The base 10 equivalent of the base 7 number 463421 is 83174.
To convert a number from base 7 to base 10, we multiply each digit of the base 7 number by the corresponding power of 7 and sum up the results.
For the number 463421 in base 7:
= 4 x 7⁵ + 6 x 7⁴ + 3 x 7³ + 4 x 7² + 2 x 7¹ + 1 x 7⁰
= 4 x 16807 + 6 x 2401 + 3 x 343 + 4 x 49 + 2 x 7 + 1 x 1
= 67228 + 14406 + 1029 + 196 + 14 + 1
= 83174
Therefore, the base 10 equivalent of the base 7 number 463421 is 83174.
Learn more about Number System here:
https://brainly.com/question/29101622
#SPJ1
50 Points! Multiple choice geometry question. Photo attached. Thank you!
The additional growth of plants in one week are recorded for 11 plants with a
sample standard deviation of 3 inches and sample mean of 10 inches.
t at the 0.05 significance level = Ex: 1.234
Margin of error = Ex: 1.234
Confidence interval = [ Ex: 12.345 Ex: 12.345 ]
[smaller value, larger value]
1. The t-value of the data is 1.833
2. The margin of error is 1.66
3. The confidence interval is between 11.66 to 8.34
What is the margin of error?From the question given;
sample size = 11
sample mean = 10 inches
standard deviation = 3 inches
1.The t-value of the data with a degree of freedom equal to 10 at 0.05 significance level = 1.833
2. Using the formula below, the margin of error is;
[tex]ME = t * \frac{SD}{\sqrt{n} }[/tex]
ME = margin of errort = t-valueSD = standard deviationn = sample sizeSubstituting the values into the formula above;
ME = 1.833 * 3/√11
ME = 1.66
3. The confidence interval of the data is;
CI = mean ± ME
where CI is the confidence interval, mean is the sample mean, and ME is the margin of error. In this case, the confidence interval is calculated as follows:
CI = 10 +/- 0.96 = 9.04 to 10.96 inches
CI = 10 ± 1.66 = 11.66 to 8.34
Learn more on margin of error here;
https://brainly.com/question/29419047
#SPJ1
The side lengths of ABC are AB = 12, BC= 19, and AC = 11. List the
angles of the triangle in order from smallest to largest.
The angles of the triangle are ordered as follows:
<B, <C and <A.
What is the law of sines?We consider a triangle with side lengths and angles related as follows:
Side length of a is opposite to angle A.Side length of b is opposite to angle B.Side length of c is opposite to angle C.Then the lengths and the sines of the angles are related as follows:
sin(A)/a = sin(B)/b = sin(C)/c.
By the law of sines, we have that the greater angle measures are opposite to the greater side lengths.
Hence the angle measures for this problem are ordered as follows:
<B -> opposite to AC = 11.<C -> opposite to AB = 12.<A -> opposite to BC = 19.More can be learned about the law of sines at https://brainly.com/question/4372174
#SPJ1
The angles of triangle ABC is arranged below
angle b - smallest
angle c
angle a - largest
How to arrange the measure of the anglesTo determine the angles of triangle ABC in order from smallest to largest, we can use use the knowledge that the side with higest length will face the largest angle.
Let the angles be
angle c is opposite AB = 12
angle b is opposite AC = 11
angle a is opposite BC = 19
Using the knowledge as introduced we have that
angle a > angle c > angle b
Learn more about triangle at
https://brainly.com/question/1058720
#SPJ1
Which graph shows the solution set for -4.421.6x-3.6?
←++
-3
←++
-3
-2 -1 0
←+++
-7
-2
-1 0
-7 -6 -5 -4
-6 -5 -4
1
1
-3
♡
2
2
3
-2
3
-2 -1
-1
The graph shows the solution set for -4.4 ≥ 1.6x - 3.6 is Graph I.
To solve the inequality -4.4 ≥ 1.6x - 3.6, we can follow these steps:
Add 3.6 to both sides of the inequality to isolate the term with x:
-4.4 + 3.6 ≥ 1.6x - 3.6 + 3.6
-0.8 ≥ 1.6x
Divide both sides of the inequality by 1.6
-0.8 / 1.6 ≥ 1.6x / 1.6
-0.5 ≥ x
So, the solution to the inequality is x ≤ -0.5.
Now, from the solution the graph for the inequality start with closed dot from 0.5 and move towards the points -0.6, -0.7, -0.8, ....
Thus, the graph shows the solution set for -4.4 ≥ 1.6x - 3.6 is Graph I.
Learn more about Inequality here:
https://brainly.com/question/20383699
#SPJ1
a triangle has angle measurements of 51 89 and 40 what kind of triangle is it?
(20 points, please answer quick)
The correct classification for this triangle is an acute triangle.
How to solveThe angle measures given are 51, 89, and 40 degrees.
There are no angles that are either equal to or greater than 90 degrees among those mentioned. Consequently, the triangle does not contain any angles that are either right or obtuse.
To categorize a triangle according to its angles, the total of the angles within the triangle, which is invariably 180 degrees, is taken into account.
51 + 89 + 40 = 180
Given that the total of the angles is 180 degrees, we can deduce that this particular triangle is acute in nature. An acute-angled triangle is a type of triangle that has three angles which are each smaller than 90 degrees.
Therefore, the correct classification for this triangle is an acute triangle.
Read more about acute angles here:
https://brainly.com/question/6979153
#SPJ1
Steve is going shopping. This matrix shows his shopping list:
How much will Steve spend if he shops at S2?
Round to the nearest cent
$27.71 is the amount Steve spend if he shops at S2.
Given that Steve is going shopping
The shopping list of steve has 2 cereal, 4 soups , 2 soda, 1 milk and 4 candy.
We have to find the cost spend by Steve when he purchase in shop 2, S2.
In S2, the cereal cost 2.15, soup cost 2.75, soda cost is 3.00, Milk cost 3.25 and candy costs 0.79.
Total cost = 2×2.15 + 4×2.75+2×3+1×3.25+4×0.79
=4.3+11+6+3.25+3.16
=27.71
Hence, $27.71 is the amount Steve spend if he shops at S2.
To learn more on Total cost click:
https://brainly.com/question/14927680
#SPJ1