Answer:
Marginal Cost = $30
Explanation:
Given that
Price = $60
Elasticity of demand = -2
Recall that
MC = P(1 + 1/Ed)
From monopolist pricing rule as a function of elasticity of demand.
Where MC = marginal cost
Ed = elasticity of demand = -2
Thus
MC = 60 (1 + 1/-2)
= 60 (1 + [-0.5])
= 60 ( 1 - 0.5)
= 60 (0.5)
= 30
MC = $30