In order to find the density of an object, maria is trying to measure its volume. however, the object does not fit in the tool she is using. to solve this problem, maria decides to break apart the object. will maria be able to find density following this method? why or why not?

yes she can. The density of a substance remains constant.

Explanation:

The density of a substance can be defined as the ration of mass upon volume. The density of a substance remains constant. This is because, with change in volume, the amount of mass contained in it also changes in the same proportion. Thus, Maria would be able to find the density of the object after breaking it.  

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.