$6-17($b$)$ Modify the original program to include the following features:

$>$ A second pump $P2(O$:$\frac{2}{2})$ that operates whenever Pl is operating.

$>$ Turn the heater $(O$:$\frac{2}{4})"$on$"$ whenever the vessel is Full.

$>$ Turn the Mixer motor $(O$:$\frac{2}{0})"$on$"$ whenever the vessel is at any level but Low.