The first figure seen below shows a surface grinder. The workpiece is oscillated under the spinning $90-$mm$-$diameter grinding wheel by the crank$-$slider linkage which has a $22-mm$ crank, a $157-mm$ connecting rod, and a $40-mm$ offset. The crank turns at $30$ rpm $,$ and the grinding wheel turns at $3450$ rpm $.$ Let ${}_2=95$ and ${}_2=0ra\frac{d}{s^2}.$ Assume the figures below show the second, or crossed, circuit of the mechanism. Determine the following:

$($a$)$ The angular acceleration of link $3,{}_3,$ using the proper units

$($b$)$ The linear acceleration of the pin at point b$,$ using the proper units

Note: an additional schematic diagram is provided below to help with this problem