You join a service center of a smartphone brand as an Operations Head. You are told about the hourly call load at the call center. You also are aware that a service executive can handle 5 calls per hour on an average. Given that any shift can start at the beginning of an hour, how shall you schedule the shift timings and roster the service executives so as to run the call center with minimum number of manpower? Assume that a shift of 9 hours in which employees work for first 4 hours, then have a break of 1 hour, and then work for next 4 hours