Figure below shows the shaft with two gears attached on it. This shaft is made of steel with E=207 GPa. The distance a=300mm and the mass ma=100kg. The mass of the shaft is neglected. The diameter of the shaft is d, which is to be determined. a) Calculate the deflections at point A (8A4 , SAR) and Point B (8BA, 8BB) because of the two gears' weights (d needs to be carried because it is a unknow variable); (8 points) b) Use Rayleigh method to compute the diameter d so that the first critical speed is 9000 rpm; (6 points) c) Use Dunkerley method to compute the diameter d so that the first critical speed is 9000 rpm; (6 points) 2 ma ma a a 300mm 3.