St. john mountain park has a bike trail up the side of the mountain. how far could you bike up and return in 3hr if you pedaled up at 5mi/he and coasted down at three times that speed?

He ! a group of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?