How many of new Silent Riders were in regular service at the moment
A. None.
B. Twenty.
C. Fifty.
D. On
According to the passage, energy is released in the Sun when ______.
A. helium atoms bind with each other
B. gamma radiation escapes from the spectrum
C. radiation is absorbed by helium
D. nuclei of hydrogen atoms collide
The passage indicates that, in comparision to radio waves, gamma waves ______.
A. produce louder sound
B. are less magnetic
C. do not form in the Sun's center
D. are not long
Which of the following countries has tile most immigrants
A. The U.K.
B. The U.S.
C. Australia.
D. New Zealand
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