Answer by JKismyhusbandbae: 6n-16
Arithmetic Formula: 
Use the following formula to determine any number in an arithmetic sequence:
an = a1 + d (n – 1)
a1 = the first term.
d = common difference
n = term number
Circumference of a circle =
(diameter)
Diameter = 23 in.
Plug in the diameter = 23 in in the formula of circumference given above
Circumference of a circle =
(23)
Circumference of a circle = 23
= 3.14
Circumference of a circle = 23 (3.14)
Circumference of a circle = 72.22 in
Option D is the answer
Using the shell method, the volume is

Each cylindrical shell has radius
(the horizontal distance from the axis of revolution to the curve
); has height
(the vertical distance between a point on the
-axis in
and the curve
).
Compute the integral.

-1
1/4×-2= -2/4 -2/4×2/1= -1