A tank in a processing unit needs to have an automatic control system installed to control...

A tank in a processing unit needs to have an automatic control system installed to control its level. Manipulating a control valve on the outlet flow of the vessel controls the level. The level must be controlled at 93 percent with an acceptable error of plus or minus 2 percent.

This is an example of:

a. A feedback control loop

b. A feedforward control loop