Temperature changes are observed over the course of three summer months and modeled by the function f (x) = 3 cosine (StartFraction pi Over 5 EndFraction x + StartFraction pi Over 5 EndFraction) + 25, where x represents the days after June 1 and f(x) represents the temperature in degrees Celsius on day x. The first occurrence of the highest temperature in the cycle is day with a temperature of °C. The first occurrence of the lowest temperature in the cycle is day with a temperature of °C.

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?