4. Annie is planning a large surprise party for her sister Gwendolyn. She has developed the plan below, including estimates of the time (in hours) and cost necessary to perform each of the activities required at the currently planned pace and at the crashed pace. a. Annie is most interested in reducing the time associated with creating the guest null list. What is the crash cost per hour for that activity? b. Annie will save $40 for every hour she can reduce from her plan. Annie has decided to crash her project and use the money she saves to purchase a larger gift for Gwendolyn. Which activity should she crash first? c. Annie has now crashed activity A by four hours at a cost of $110. What other activity could she crash to further reduce the project? d. Annie has now crashed activity A by four hours at a cost of $110 and activity E by two hours at a cost of $75. What other activity could she crash to further reduce the project? e. How much money did Annie save by crashing the project? f. What is the duration of the fully crashed project