Please help me with this :) and please also put detailed description!

The circumference of a redwood tree trunk is 20π ft, and it is 100 ft tall. what is the approximate volume of the redwood tree trunk? 1,000π ft3 10,000π ft3 4,000π ft3 40,000π ft3

Witch represents the inverse of the function f(x)=1/4x-12

The following hormone had their receptors in the cell membrane except a-insulin b-tsh c-gh d- cortisol