Passage 3 \^6 [^\@[
In science, a theory is a reasonable explanation of observed events that are related. A the-ory often involves an imaginary model that helps scientists picture the way an observed event could be produced. A good example of this is found in the kinetic molecular theory, in which gases are pictured as being made up of many small particles that are in constant motion. a4UwhbH
A useful theory, in addition to explaining past observations, helps to predict events that have not as yet been observed. After a theory has been publicized, scientists design experi-merits to test the theory. If observations confirm the scientists’ predictions, the theory is sup-ported. If observations do not confirm the predictions, the scientists must search further. There may be a fault in the experiment, or the theory may have to be revised or rejected. /4O))}TX
Science involves imagination and creative thinking as well as collecting information and performing experiments. Facts by themselves are not science. As the mathematician Jules Henri Poincare said: "Science is built with facts just as a house is built with bricks, but a collection of facts cannot be called science any more than a pile of bricks can be called a house." Most scientists start an investigation by finding out what other scientists have learned about a particular problem. After known facts have been gathered, the scientist comes to the part of the investigation that requires considerable imagination. Possible solutions to the problem are -i?gYF!G
formulated. These possible solutions are called hypotheses. tAq0Z)
In a way, any hypothesis is a leap into the unknown. It extends the scientist’s thinking beyond the known facts. The scientist plans experiments, performs calculations, and makes ob-servations to test hypotheses. For without hypotheses, further investigation lacks purpose and direction. When hypotheses are confirmed, they are incorporated into theories. T1qbb*
11. The word "this" in the 3rd sentence in paragraph 1 refers to ______. YyYZD{^
A) a good example B) an imaginary model #f"eZAQ {
C) the kinetic molecular theory D) an observed event _cvX$(Sg
12. Bricks are mentioned in the 3rd paragraph to indicate how ____. .8W-,R4
A) mathematicians approach science Y_Fn)(
B) building a house is like performing experiments :+6W%B
C) science is more than a collection of facts nQQHm6N
D) scientific experiments have led to improved technology mDK*LL5]W
13. In the last paragraph, the author refers to a hypothesis as "a leap into the unknown" in or- der to show that hypotheses ______. nHm29{G0
A) are sometimes ill-conceived B) can lead to dangerous results @]q^OMLY
C) go beyond available facts D) require effort to formulate ,z.l#hj,{
14. What is a major function of hypotheses as implied in the last paragraph7 G+N1#0,q
A) Sifting through known facts. [ne51F5_
B) Communicating a scientist’s thoughts to others. \_O#M
C) Providing direction for scientific research. g,]o+nT
D) Linking together different theories. *VhEl7
15. Which of the following statements is supported by the passage? eMnK@J
A) Theories are simply imaginary models of past events. z |llf7:
B) It is better to revise a hypothesis than to reject it. h_?`ESI~
C) A scientist’s most difficult task is testing hypotheses. wp&G