[填空题]
Early test flights for the space shuttle used a ((0j nihdoqzk ss6t7ge1-x1)m qfpj/“glidep v+w/tp(e o)as5x 7tyr” (mass of 980 kg including pilot) that was launched horizontally at 500km/h from a height of 3500 m. The glider eventually landed at a speed of 200km/h (a) What would its landing speed have been iexto5/y7sp( w a)pt v+n the absence of air resistance?$\approx$ km/h
(b) What was the average force of air resistance exerted on it if it came in at a constant glide of 10 $^{\circ} $ to the Earth?$\approx$ N
