True/False, Explain: For each of the following statements, indicate True or False and briefly explain your answer.

(a) (5 points) If market demand for an illegal drug is inelastic then a government intervention that increases the price of illegal drugs will increase drug dealer revenues.

(b) (5 points) For linear demand, the slope and the elasticity are identical at any given price.

(c) (5 points) Studies have estimated the cross-price elasticity of demand of steak and scallops to be -0.10. This means that steak and scallops are substitues.

(d) (5 points) In 1970, an art collector paid $10,000 for an Andy Warhol painting. Warhol's paintings have risen in value since then. True or False: The opportunity cost of owning the painting this year is the interest the collector could have received on the $10,000 invested in the painting?