a 1500 foot long trench is to be excavated with a power hoe to an average depth of 8ft. The base width of the trench is 4ft, the sides of the trench are vertical for the bottom 5ft. The top 3ft of the trench banks are sloped at a 1 to 1. The power hoe can excavate 35 cy per hour, how many hrs will it take to excavate the trench?

a 1500 foot long trench is to be excavated with a power hoe to an average depth of 8ft. The base width of the trench is 4ft, the sides of the trench are vertical for the bottom 5ft. The top 3ft of the trench banks are sloped at a 1 to 1. The power hoe can excavate 35 cy per hour, how many hrs will it take to excavate the trench?