If possible, use excel to solve. thanks :)

Problem 1 To get some more practice out of using the z-score tables, let's do some more problems with our sample project (recall the critical path has mean 23 weeks with a standard deviation of 2.4095 weeks). a) What is the probability the project will require 26 weeks or more? b) What is the probability the project will require 21 weeks or more? c) What is the probability the project will require between 23 and 28 weeks? d) What is the probability the project will require between 20 and 25 weeks? e) Let's try working in reverse. The probability of completing the project in X weeks or less is 90% : what is X