The water level in Ricky Lake changes at an average of −12inch every 3 years. Based on the rate above, how much will the water level change after 7 years?

42. if 20 men can eat 200 kg of wheat in 40 days, then 10 men can eat 300 kg of wheat in how many days? a) 120 days b) 60 days c) 80 days d) none of these