At a certain stage of the above turbine, the pressure of steam is 1 kgf / cm2 abs. moving with a velocity of 200 m/s and it is dry saturated. If the blade exit angle is 20° and the ratio of the blade speed to steam speed is 0.7, find the mean diameter of the rotor of this stage and also the rotor speed. Assume the blade height as 
of the mean drum diameter and neglect the thickness of the blades. The velocity diagrams for the blades are symmetrical.