In a pin jointed four bar mechanism ABC, the lengths of various links are as follows: AB=25 mm: BC=87.5 mm: CD=50 mm and AD=80 mm. The link AD is fixed and the angle BAD = 135. If the velocity of B is 1.8 m/s in the clockwise direction, lind 1. velocity and acceleration of the mid point of BC, and 2. angular velocity and angular acceleration of link CB and CD.