The length of runway is increased per 300 m rise above M.S.L. A. 3 % B. 4 % C. 5 % D. 7 %

The correct answer is: 3%.

The length of a runway is increased by 3% for every 300 meters of rise above sea level. This is because the air is thinner at higher altitudes, which means that airplanes need to take off and land at a higher speed. The extra length of the runway allows airplanes to reach the required speed before they take off or land.

Option A: 3% is the correct answer.

Option B: 4% is incorrect. The length of the runway is increased by 3%, not 4%.

Option C: 5% is incorrect. The length of the runway is increased by 3%, not 5%.

Option D: 7% is incorrect. The length of the runway is increased by 3%, not 7%.