Solve a(b-c)=a/b for c

An architect is designing a water fountain for a park she uses the given function to model the water jet flowing from the fountain nozzles where h(x) gives the height of the water jugs in feet x feet from the starting point h(x)=-1/20x+x+15

Find the measure for the angle indicated in bold

If a sprinkler waters 1 over 12 of a lawn in 1 over 2 hour, how much time will it take to water the entire lawn? (5 points) 10 hours 6 hours 1 over 6 hour 7 over 12 hour