The amount of matter in an object is its a. volume b. density c. mass d. charge

mass

Explanation:

the matter is measured in kg or lb and we can use a scale in order to obtain it.  This parameter is called "the mass of an object"

with 5 seconds, no, but over time if the police car stays at 65m/s ad the speeding car stays at 60, then obviously yes, but the answer to your question would be, no.

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