How would I answer this question?

Aiden buys two bags of chips at $1.09 each and a 20 ounce soda for $1.20 at the gas station.he knows that the state tax is 5.5. how much change will he receive from a $5 bill?

Janet drove 300 miles in 4.5 hours. write an equation to find the rate at which she was traveling

What is the greatest number of parts of a circle that can be formed by cutting the circle with 7 straight cuts? (note: the parts do not have to be equal in size)