While analyzing the landing procedures of airplanes, george noted one plane at an altitude of 5,000 feet descending at a rate of 300 feet per minute and one at an altitude of 14,000 feet descending at a rate of 1,200 feet per minute. which of the following solutions represents when the two airplanes will reach the same altitude? (6, 3200) (10, 2000) (12.7, 1190) (21, 1300)