There are two firms of equal size (Firm A and Firm B) operating in a market whose annual demand has recently changed. The new annual demand is...

There are two firms of equal size (Firm A and Firm B) operating in a market whose annual demand has recently changed.  The new annual demand is depicted below.  Each firm faces constant Marginal Costs of $4 per unit, with zero fixed costs (for simplicity).

pls see attachment, thank you!