A crushing circuit consists of a primary jaw crusher, a screen, and a secondary cone

crusher. The primary crusher is located adjacent to the pit and is in open circuit,

with the crusher product being conveyed to the plant. In the plant, this material is

fed into the cone crusher, which is in closed circuit with a screen which takes the

product from this crusher. The product from this circuit is the feed to the mill circuit:

a$)$ Draw the circuit, labelling streams and items.

b$)$ Why might it be advantageous to locate the primary crusher near the pit?