(i) When the demand function is 2Q - 24 + 3P = 0, find the marginal revenue when Q=3.
(ii) Given the demand function 0.1Q - 10 +0.2P + 0.02P2 =0, calculate the price elasticity of demand when P = 10.
(iii) If supply is related to the price the function P = 0.25Q + 10, find the price elasticity of supply when P = 20.
(iv) Given the demand function aQ + bP - k = 0, where a, b and k are positive constants, show that price elasticity of demand is minus one when MR = 0.
(v) when the demand is P = 20/(4 +Q), calculate the price elasticity of demand when P = 4.