Please solve! I will give brainiest.

What is 7/81 as a percentage? round your answer to the nearest tenth of a percent.

When amy exercises in her fitness center for 1 hr she burns a total of 475 calories.if she burns 9 calories a minute jogging on the treadmill and then burns 6.5 calories a minute pedaling on the stationary bicycle how many minutes of the hour does she spend exercising on the bicycle?

Explain how a credit card works when a customer makes a purchase