During a violent thunderstorm, hail the size of marbles (diameter = 0.800 cm) falls at a speed of 13.0 m/s. There are estimated to be 135.0 hailstones per cubic meter of air. Assume that, as for ice, 1.00 cm3 of hail has a mass of 0.920 g.The mass of each hailstone is 2.4664×10-4 kg. What is the magnitude of the force exerted by the hail on a 13.00 m x 12.00 m flat roof during the storm ? Ignore the bounce of the hail on impact.