Given a demand function Q = f(P), the own price elasticity of demand is defined as E : ( 28 ) . (5 ). What is the own price elasticity of demand (a) for the linear demand function Q = 100 - 5P when P = 10. (b) for the linear inverse demand function P = 100 - 4Q when (i) Q = 10 ; (ii) Q = 20 ; (iii) Q = 12.50. (c) for the demand function Q = p-0., when () Q = 100; (ii) Q = 20. (d) for the inverse demand function P = 5Q-1 , when (i) Q = 10; (i) Q = 20