Oshana Construction has just signed a contract with Tangi Enterprises for the construction of a machine. The management accountant constructed the following network diagram for the project The duration and variable cost under normal and accelerated circumstances of the various activities are as follows: Activity Estimated time (hours) Estimated variable implementation costs Cost slope N$ Normal Accelerated Normal (N$) Accelerated (N$) A B A C B C B D C E D E 96 95 0 48 128 125 64 90 0 32 ? 85 224 000 120 000 0 110 000 172 000 133 000 308 000 135 000 0 126 000 193 600 193 000 2 000 ? 0 1 000 1 200 1 500 779 000 955 600 The accelerated duration of activity CE is uncertain. The estimated hours are as follows: Most optimistic time 98 hours Most likely time 107 hours Most pessimistic time 134 hours Fixed costs are absorbed at a rate of N$1 750 per hour and are not regarded as committed fixed costs. Other direct costs for the project amount to N$250 000. Required Marks Sub total Total 4.1 Calculate the cost slope for activity AC. 2 2 4.2 Calculate the expected duration of the accelerated/crash activity CE. 3 5 4.3 Calculate the duration of the various routes and determine the critical path. 2 7 4.4 Set out the programme to be followed in order to reduce total project time in the most cost efficient manner and state the number of hours for completion of the project that will ensure minimum total costs. 15 22 4.5 Calculate the accelerated/crash cost of the project.