The time (in minutes) required to complete a certain subassembly is a random variable X with the density function f(x) = 1/21 x^2, 1 ≤ x ≤ 4. (a) Use f (x) to compute Pr(2 ≤ X ≤ 3). (b) Find the...

The time (in minutes) required to complete a certain subassembly is a random variable X with the density function f(x) = 1/21 x^2, 1 ≤ x ≤ 4.
(a) Use f (x) to compute Pr(2 ≤ X ≤ 3).
(b) Find the corresponding cumulative distribution function F(x).
(c) Use F(x) to compute Pr(2 ≤ X ≤ 3).