The Budd Gear Co. specializes in heat-treating gears for automobile companies. At 8:00 a.m., when Budd's shop opened today, five order (listed in order) were waiting to be processed.

Order Order size (Units) Per Unit Time in Heat Treatment (minutes/unit) Due Date (Min. from now)

A 16 4 160

B 6 12 200

C 10 3 180

D 8 10 190

C 4 1 220

a. If the earliest due date is used, what sequence should be used?

b. What will be the average job tardiness?

c. What will be the average number of jobs in the system?

d. Would the Shortest processing time rule produce better results in terms of average job tardiness?

_____new average job tardiness is______minutes