Problem $15\mathrm{.}66$ modified

Robert's linkage is named after Richard Robert $(1789-1864)$ and can be used to draw a close approximation to a straight line by locating a pen at point $F.$ The distance $AB$ is the same as $BF,DF$ and $DE.$ It is known that the angular velocity of bar $AB$ is $5\mathrm{.}0ra\frac{d}{s}$ clockwise in the position shown.

Determine the angular velocity of plate $BDF.{}_{BDF}=q,k(ra\frac{d}{s})$

Determine the angular velocity of bar $DE*{}_{DE}=$ k $($rad$/$s$)$

Determine the velocity of point $F*v_F=q,1+$ j $($in$./$s$)$