What effect, if any, does each of the following events have on the price elasticity of demand for corporate-owned jets?

a. Reduced corporate earnings lead to cuts in travel budgets and increase the share of expenditures on corporate jet travel.

b. Further deregulation of the commercial airlines industry substantially increases the variety of departure times and destinations offered by commercial airlines.

c. The cost of manufacturing corporate jets rises.

d. A new, much more fuel-efficient corporate jet is introduced.