$($a$)$ Surface defects have been counted on $25$ rectangular steel plates as shown below :

$\backslash$table$[[1,2,3,4,5,6,7,8,9,10,11,12,],[1,0,4,3,1,2,5,0,2,1,1,4,],[13,14,15,16,17,18,19,20,21,22,23,24,25],[0,8,0,2,1,3,5,4,6,3,1,0,2]]$

Comment on the statistical control of the process. If the process requires further modification, make necessary modifications $"$to bring the process within control.