Calm period is the percentage of time during which wind intensity is less than

A. 78 m B. 150 m C. 300 m D. 450 m

A. Asphaltic concrete B. Rubberised tar concrete C. Plain concrete D. All the above

A. Ends of the runway B. Point of intersection of the obstruction clearance line and the extended plane of the runway surface, and the other end of the runway C. Point of intersection of the glide path and the extended plane of the runway surface and the other end of the runway D. Ends of the clear way on either side

A. 22.5 m × 22.5 m B. 30 m × 30 m C. 22.5 m × 30 m D. 60 m × 120 m