can somone help me find the average number of jobs in the ststem

Henri's Custom Gowns has six jobs waiting to be processed. Each gown is at the beading work center. The job information is shown here. Henri has decided to try a different priority rule. Based on the sequence developed in part (a), calculate the following performance measures: makespan, mean job flow time, average number of jobs in the system, mean job lateness, mean job tardiness, and maximum tardiness, "(Round your answers to 2 decimal ploces, es. 1.75. If entering a negative number use the () sign.)