Hiya!
16.) If you have 3.2 L, and you need mL, move the decimal to the right. It becomes 3,200 mL. So, the answer is B.).
18.) Your answer is A.). 1,000 m is in one kilometer.
21.) Not sure at all! Ask your teacher, or try looking up what hectometers are. Is that ten meters? If so, the answer is A.), I believe.
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