(just need part B thank you)

Problem 21 Question Help Recently, you were assigned to manage a project for your company. You have constructed a network diagram depicting the various activities in the project (shown below to the right). In addition, you have asked your team to estimate the amount of time that they would expect each of the activities to take. Their responses are shown in the following table: Time Estimates (days) Optimistic Most Likely Pessimistic Activity A 6 7 10 B 3 7 12 Start Finish 4 5 8 D 1 4 5 B E 5 7 9 a. What is the expected completion time of the project? The expected completion time is 18 days. (Enter your response as an integer.) b. What is the probability of completing the project in 20 days? Refer to the standard normal table. The probability of completing the project in 20 days is (Enter your response rounded to four decimal places.)