Plz help me with these, I don't understand this subject.

If you answer 2+2 you will get over 80 points

There were 25 students who answered to a survey about sports. four-fifths of them like football. how many students like football?

To convert celsius temperatures to fahrenheit, you can use the expression (c + 32). tom says that another way to write this expression is c + 32. what error did tom make?