单项选择题Every chemical change either results from energy being used to produce the change, or causes energy to be ______ in some form.

A.given off
B.put out
C.set off .
D.used up


延伸阅读

你可能感兴趣的试题

1.单项选择题These goods are ______ for export, though a few of them may be sold on the home market.

A.essentially
B.completely
C.necessarily
D.remarkably

3.单项选择题It is ______ of you to turn down the radio while your sister is still iii in bed.

A.considerable
B.considerate
C.concerned
D.careful

5.单项选择题By 1929, Mickey Mouse was as popular ______ children as Coca-Cola.

A.for
B.in
C.to
D.with

6.单项选择题Because Edgar was convinced of the accuracy of this fact, he ______ his opinion.

A.struck at
B.strove for
C.stuck to
D.stood for

7.单项选择题My students found the book ______; it provided them with an abundance of in- formation on the subject.

A.enlightening
B.confusing
C.distracting
D.amusing