Carbon dioxide.. Animals use energy, breathe oxygen, and drink water..
They changed things up because its mixed or from up further in the family line. like your parents could have green eyes and you could get blue. it shoukd of came from your grandparents or other blood related relatives.
you see katie helped sandra with homework, which helped sandra not fail. Because katie did not let sandra fail, sandra can graudate and get a job. She can also thank katie for not letting sandra fail and go homeless.
sandra helped katie rollerblade. which has no significant impact. Who cares about rollerblading.
your answer is C
