1. Given the demand function Qd = -4P +180 and the supply function Qs = 2P - 20, mathematically determine the amount of total revenue this firm will make when it sells it's good at market price (round to two decimals).

a. Using the demand equation from number 1, determine the price elasticity of demand when price rises from $30 to $35 using both the midpoint method and are the point to point method.