You can try as hard as you like but you won’t succeed
A.However hard you try, you won’t succeed
B.You can hardly try as you like, but you won’t succeed.
C.You won’t succeed because you can’t try as hard.
D.Although you won’t succeed, you can try as hard as you like.

If we had lost the map, we would never have found our way.
A.We will find our way unless we lose the map.
B.We didn’t lose our way because we didn’t lose the map.
C.We would have lost our way provided we had lost the map
D.Supposing we lose the map, we would not find our way.

We can conclude from the passage that Marian Anderson first toured Europe instead of the United States because __________ .
A.it was too expensive to tour in the United States
B.she was paid more in Europe
C.she was not allowed to perform in the United States
D.there were better operatic facilities in Europe

The word "barred" could best be replaced by which of the following?
A.purged
B.released
C.prohibited
D.overpowered

The phrase "broke down . . . barriers" means ________ .
A.disclosed opportunities
B.shattered obstacles
C.revealed inaccuracies
D.analyzed destinations

The word "eventually" could best be replaced by which of the following?
A.later
B.at last
C.in the long run
D.recently

What is the main topic of this passage?
A.the nature of radar
B.types of ranging
C.alternatives to radar
D.history of radar

The word “dense” could be replaced by __________ .
A.cold
B.wet
C.dark
D.thick

Which of the following words best describes the tone of this passage?
A.argumentative
B.imaginative
C.explanatory
D.humorous

Which type of waves does radar use?
A.sound
B.heat
C.radio
D.light