Solve the following three problems by Instantaneous Centre Method

Q$\mathrm{.}1.$ In a four link mechanism the crank AB rotates at $36$ radians per second. The lengths

of the links are A B $=2000$ mm; BC $=400$mm$,$ CD $=450$ mm and AD $($fixed link$)=$

$600$ mm$.$ At the instant when AB is at right angles to AD$,$ determine the velocity of:

$($i$)$ the mid point of link BC $($ii$)$ a point on the link CD$,100$ mm from the pin connecting

the links CD and AD$.$