Activity optimistic Most pessimistic 25 Show detail work calculating the mean activity time and variance for both activities from above. NormalCrash Immediatel Activity Tim Cost from Cost Predecessors ISIS 000S 7,000 3 $4.000 2 4 ,000 - 1 Iskis. S SIS.000 2 $3.000 1 3.500A.B.C 12 ISI 500 IS 2.400 CD 14 $4.000 IS 7,000A S $7.000 4 12.000 DF 758,000 $20,000E For this problem, I ask that we all use the same variables for each activity as described on the powerpoint. For example, each activity has two variables, an "X" and a "Y" variable. Activity A's two variables would be Xa and Ya. Write two of the activity constraints (only two) for the above crashing problem assuming it needs to be crashed to 14 units of time. (Write out the original constraints, then make sure and apply algebra to the constraints) Write two of the constraints (only two) for the above crashing