please help, thanks

A U.S. Postal Semice supervisor is looking for ways to reduce stress in the sorting department. With the existing arrangement, stamped letters are machine-canceled and loaded into bubs with 325 letters per tub. The tubs are then pushed to postal clerks, who read and key zip codes into an automasod sorting machine at the rate of one tub per 425 seconds. To overcome the stress caused When the stamp canceling machine outpaces the sorting deeks, a pult system is proposod. When the clerks are ready to procoss another tub of mal, thoy wil pull the tub from the canceling machine area. How many tube should dralate between the sorting clerks and the canceling machine if 75.000 letters are to be soted during a 10 -hour shint, the satoty stock policy variable. a. is 0.10 , and the arerege waiting time plus materail handing time is 45 minutes per tub? The average processing time per tib of letsen. p, is day, (Enter your response rounded to four decima places) The average wating time per hb of lethers, w is day. (Entor your response mounded no four decimal paceu) Theretore, the number of tubs that chould dirculahe between the sortng derks and the canceling machine is tubs. (Enter your fosponse rounded up to the pext whale number