The demand function for VCRs has been estimated to be
Qv = 134 - 1.07Pt + 46Pm - 2.1Pv - 5M,
where Qv is the quantity of DVD players, Pt is the price of a DVD, Pm is the price of a theater movie ticket, Pv is the price of a DVD player, and M is income. Based on this information, answer the following questions.
a. Are DVD players normal or inferior goods?
b. Are theater movies substitutes or complements for DVD players?
c. What additional information is needed for you to be able to calculate the price elasticity of demand for DVD players?