14.
A. They held more positive attitudes toward life.
B. They could do more challenging tasks.
C. They found it easier to focus on work at hand.
D. They could keep on working longer.
13.
A. It is most important to have confidence in one's willpower.
B. Most people get energized after a sufficient rest.
C. Most people tend to have a finite source of energy.
D. It is vital to take breaks between demanding mental tasks.
Questions 12 to 15 are based on the passage you have just heard.12.
A strong determination.
B. A good start.
C. A detailed plan.
D. A scientific approach.
11.
A. It is second only to the Mississippi River in width.
B. It has numerous human settlements along its banks.
C. It carries about one fifth of the world's fresh water.
D. It is as long as the Nile and the Yangtze combined.
10.
A. It has not yet been fully explored and exploited.
B. It provides habitats for more primitive tribes.
C. It is hardly associated with great civilizations.
D. It gathers water from many tropical rain forests.
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