$7.)$An express checkout line at a grocery store takes an average of $3$ minutes to ring up a customer's order. On average, nine customers are in the checkout line. What is the average number of customers per hour processed in the checkout line? Assume that there are multiple express check out lines in the store. Round your answer to the nearest whole number.

$8.)$An accounts receivable manager processes $220$ checks per day, with an average processing time of $12$ working days. What is the average number of accounts receivable checks being processed in her office? Round your answer to the nearest whole number.

WIP $(12$ days$)$: checks

What is the average number of accounts receivable checks being processed if$,$ through information technology, she reduces the processing time from $12$ days to $8$ days? To $4$ days? Round your answers to the nearest whole number.

WIP $(8$ days$)$: checks

WIP $(4$ days$)$: checks