1.6 × 1.6 × 1.6 × 1.6 = 6.5536
Well.
The relation between the circumference of a circle and its diameter is described by the following equation:

where d is the diameter of the circle.
For a giving diameter (d=3ft), we can substitute in the previous equation
The circumference of a circule= 3.14*3 (you can use ur calculator to find the exact number i guess it will be about 9.42 ft)
I hope it helps.
Answer: Choice A. (8, 4)
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Explanation:
Because x = 2y, we can replace every copy of x with 2y
Let's do so in the second equation
3x - 4y = 8
3(x) - 4y = 8
3(2y) - 4y = 8 .... x replaced with 2y; now let's isolate y
6y - 4y = 8
2y = 8
y = 8/2 ..... divide both sides by 2
y = 4
Use this y value to find x
x = 2y
x = 2*4
x = 8
So we have x = 8 and y = 4 pair together to get the answer (x,y) = (8, 4) which is choice A.
C. just shorten fraction and you'll only get 1/(y²z²)
you'll get (6xy²z²)/(6xy⁴z⁴)=1/(y²z²)