mr trocki is the groundskeeper for a vacation resort. he has programmed the sprinkler system to run at night in three different zones. The sprinklers turn on at midnight and run until 7am. the fist zone runs every 90 minutes, the second zone turns on every 40 minutes, and the third zone turns on every 45 minutes. write a work problem within the context of the vacation resort that can be solved by determining the GCF