For the following control systems, draw a block diagram of the following scenario and identify one (1) possible controlled variable, manipulated variable(s), and disturbance variable(s). Explain why you identify such disturbance variable(s).

Case Scenario	Controlled Variable	Manipulated Variable	Disturbance Variable	The explanation why you identify such disturbance variable(s)	Controller Type
a) controlling the water level in a toilet tank
b) a security lighting system that activates at dusk and turns off at dawn