Wuts the answer to this equation?

17 - 5 x 4 ÷ 2

If a baby uses 15 diapers in 2 days, how many diapers will the baby use in a year?

Yesterday i ran 5 miles. today, i ran 3.7 miles. did my percent increase, decrease or is it a percent error? plz i need

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?