Please help me with this

Can someone me and do the problem plz so i can understand it more better

Acylinder with a base diameter of x units has a volume of jxcubic units which statements about the cylinder are true? check all that apply. the radius of the cylinder is 2 x units. the radius of the cylinder is 2x units. the area of the cylinder's base is 200 square units. the area of the cylinder's base is a square units. the height of the cylinder is 2x units. the height of the cylinder is 4x units. mark this and return save and exit next submit

For f(x) = 3x+1 and g(x) = x2 - 6, find (g/f)(x)