Barter usually takes the place of money transaction where______.
A. there is only salt
B. metal tools are used
C. the people's trading needs are fairly simple
D. money is unheard of
In the middle of the second paragraph the word "intentionally" means______.
A. purposely
B. dangerously
C. carefully
D. carelessly
A．dealB．numberC．mountD．amount
A. deal
B. number
C. mount
D. amount
Galileo studied medicine in the university at Pisa.
A. True
B. False
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