I cannot solve these two problems and do not know where to start. please help. thanks. 1. A 77 kg man drops to a concrete patio from a window only 0.45 m above the patio. He neglects to bend his knees on landing, taking 2.0 cm to stop. (a) What is his average acceleration from when his feet first touch the patio to when he stops? (b) What is the magnitude of the average stopping force? 2. Imagine a landing craft approaching the surface of the moon of a distant planet. If the engine provides an upward force (thrust) of 2910 N, the craft descends at constant speed; if the engine provides only 2200 N, the craft accelerates downward at 0.47 m/s2. (a) What is the weight of the landing craft in the vicinity of moon's surface? (b) What is the mass of the craft? (c) What is the magnitude of the free-fall acceleration near the surface of the moon?