Find the volume of the sphere. Either enter an exact answer in terms of π or use 22/7 for π.

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

Solve for the equation. 4x - 13 = 2x + 9

If f(x)=x^2- 4 and g(x)=x^2 plus 2 x, (c) (f-/3) = ? (simplify your answer.)