A manufacturer's average work-in-process inventory for Part #1234 of a particular car model is 1,250 parts. The workstation produces parts at the rate of 150 parts per day. What is the average time a part spends at the workstation?
a. More than 4 but less than or equal to 6 days.
b. More than 6 but less than or equal to 8 days.
c. More than 8 but less than or equal to 10 days.
d. More than 10 days.