For one of his courses, tom has to read a book. He can read 1 page per minute. Tom's boss has agreed that tom could use his idle time for studying, as long as he drops the book as soon as a call comes in. How many pages can tom read during an 8-hour shift?
b. How long does a customer have to wait, on average, before talking to tom?
c. What is the average total cost of telephone lines over an 8-hour shift? Note that the department store is billed whenever a line is in use, including when a line is used to put customers on hold. (hint: at any given time, what is the average # of callers? Each caller in the system, either waiting or being served, occupies a line, and therefore, incurs cost for the department store.)