In the late 1990s, the television networks were given

$70 billion worth of space on public airways for broadcasting high-definition television rather than auctioning it off.

a. Why do airways have value?

b. After the airway had been given to the network, would you expect that the broadcaster would produce high-definition television?

c. How might a drug company in the United States encourage a doctor in the United States, where doctors receive nothing for drugs, to prescribe more drugs?