Find the circumference of a circle whose area is 452.16 square meters. (use 3.1416 as the value of .)
a. 12 meters
b. 37.6992 meters
c. 24 meters
d. 75.3984 meters

9. what is the volume of a cube shaped box with edges 6 cm. in length?
a. 216 cu. cm.
b. 1,296 cu. cm.
c. 36 cu. cm.
d. 18 cu. cm.

1) The area of a circle is given by

where r is the radius of the circle. In this problem, we are told that the area is

so we can rearrange the previous equation to calculate the radius:

And now we can find the circumference, by using the formula:

Therefore, the correct answer is D. 75.3984 meters.

2) The volume of a cube is given by:

where L is the length of the edge. In this problem, L=6 cm, therefore the volume of the cube is

and so, the correct answer is A. 216 cu. cm.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.