Acylindrical metal pipe has a diameter of 20 millimeters and a height of 21 millimeters. a cylindrical hole cut out of the center has a radius of 6 millimeters. which expressions represent the volume of metal needed, in cubic millimeters, to make the pipe? check all that apply. 21π(10)2 – 21π(6)2 π(20)2(21) – π(6)2 2,100π – 756π 7,644π
1,344

Options A and C are correct choices.

Step-by-step explanation:

We have been given that a cylindrical metal pipe has a diameter of 20 millimeters and a height of 21 millimeters. A cylindrical hole cut out of the center has a radius of 6 millimeters.

We will use volume of cylinder formula to solve our given problem.

, where,

r = Radius of cylinder,

h = height of cylinder.  

The volume of the cylinder will be equal to volume of cylinder with radius of 10 mm (20/2) minus volume of cylinder with radius of 6 mm.

Therefore, option A is the correct choice.

Therefore, option C is the correct choice as well.

x is the total time in minutes for the free response

you are given number of questions as 15 - m and time per item as 8 minutes

to find x multiply the two givens together:

x = 8 * (15-m) = 8(15-m)