A rock is thrown into a pool 72 inches deep. The rock sinks at a rate of 4 inches per second (s). The rock's height (h) above the bottom of the pool is given by the
equation: h = 72 – 4s. After how many seconds will the rock be half way to the
bottom?

Using pert, adam munson was able to determine that the expected project completion time for the construction of a pleasure yacht is 21 months, and the project variance is 4. a) what is the probability that the project will be completed in 17 months? b) what is the probability that the project will be completed in 20 months? c) what is the probability that the project will be completed in 23 months? d) what is the probability that the project will be completed in 25 months? e) what is the due date that yields a 95% chance of completion?