Generate a sentence that answers this question: "Pulse rate increases".

Answer: as energy required for an activity increases , pulse will increase

Generate a sentence that answers this question: "Friction might be".

Answer: friction occurs when two object 's surfaces move against each other

Generate a sentence that answers this question: "Over the years, the desert rat has evolved traits that help it live with low supplies of water, what is this an example of?".

Answer:
an organism 's environment affects that organism 's acquired characteristics