I really do not have any information .This is an homewok that I have got . Actullay this question from Facility planning

3. A construction firm is working on a roadway for which dump trucks and power shovels are the primary equipment being used. Time studies reveal the following time values (minutes) Time to load a truck 15 Travel time to dumping point 15 Dumping time 3 Return time 13 (a) What is the minimum number of trucks that will prevent idle time on the part of the power shovel? (b) Suppose that it costs $25 per hour to operate the power shovel and $15 per hour to operate each truck. How many trucks should be assigned to the job to minimize the cost per truck load hauled? (c) Construct a man-machine chart for the most economical arrangement between dump trucks and the power shovel