operation management....

A single machine work center has five jobs assigned to it. They are labeled, in the order of their arrival in the shop, as jobs A, B, C, D and E. The work center may work on only one job at a time and must complete any job it starts before starting another job. Job A has a processing time of 6 days and is due to the customer in 9 days. Job B has a processing time of 2 days and is due in 16 days. Job C has a processing time of 4 days and is due in 10 days. Job D has a processing time of 3 days and is due in 7 days. Job E has a processing time of 5 days and is due in 12 days. Using the first-come-first-served priority rule, what is the number of late (tardy) jobs?