(D) The biggest growth in sales in the manufacturing sector has come in industries that market the most innovative products.
(E) Recent improvements in management practices have allowed many manufacturers to experience enormous gains in worker productivity.
Questions 4-5 refer to the following.
If the airspace around centrally located airports were restricted to commercial airliners and only those private planes equipped with radar, most of the private-plane traffic would be forced to use outlying airfields. Such a reduction in the amount of private-plane traffic would reduce the risk of midair collision around the centrally located airports.
4. The conclusion drawn in the first sentence depends on which of the following assumptions?
(A) Outlying airfields would be as convenient as centrally located airports for most pilots of private planes.
(B) Most outlying airfields are not equipped to handle commercial-airline traffic.
(C) Most private planes that use centrally located airports are not equipped with radar.
(D) Commercial airliners are at 美国GREater risk of becoming involved in midair collisions than are private planes.
(E) A reduction in the risk of midair collision would eventually lead to increases in commercial-airline traffic.
5. Which of the following, if true, would most strengthen the conclusion drawn in the second sentence?
(A) Commercial airliners are already required by law to be equipped with extremely sophisticated radar systems.
(B) Centrally located airports are experiencing over-crowded airspace primarily because of sharp increases in commercial-airline traffic.
(C) Many pilots of private planes would rather buy radar equipment than be excluded from centrally located airports.
(D) The number of midair collisions that occur near centrally located airports has decreased in recent years.
(E) Private planes not equipped with radar systems cause a disproportionately large number of midair collisions around centrally located airports.