Do number 3 correctly and pls explain how to do (steps) i will give you 15 points and do number 4 pls

The answer to question 3 is D because what you want to do is find how many kilometers you can travel in 2½ hours going at the speed of 275 kilometers per hour. So that one is just simple multiplication. The next one is simple division. So what you have to do is find how many miles she can go per gallon. You would divide  420 by 8.75, which is the same as 8 3/4. That way you would get the answer 48 miles per gallon. I hope this helped!