An image of a cue ball striking the surface of a pool table is shown. all of the following describe the acceleration of the cue ball except -

the ball changed direction when it hit the side of the table.

the ball traveled at 30 cm/s while it was moving.

the ball was at rest until it was struck by the pool cue.

the ball eventually came to a stop due to friction.

the answer is the

astronomers such as edwin hubble.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.