(Answered) how does cost affect equilibrium quantity and efficient quantityhow does cost affect equilibrium…

➤ Why might the equilibrium quantity differ from the efficient quantity?
Private equilibrium differs from efficient quantity when markets ignore external costs or benefits. The efficient output occurs where marginal social benefit equals marginal social cost. Market equilibrium instead equates private marginal benefit and private marginal cost, causing deadweight loss when externalities, public goods, or market power are present.