30. Chicago is the third largest publishing center in the United States,
A B C
exceeding only by New York City and San Francisco.
D
31. North American bison differ from domestic cattle in have 14 rather than 13
A B C D
pairs of ribs.
32. Female sea turtles, before laying her eggs, swim as much as 2,000 kilometers
A B
to return to the beaches where they themselves were hatched.
C D
33.
Water is the only substance that occur at ordinary temperatures in all three
A B C
