Can someone help me out please, like asap!

Tod does not have any cookies. david gives jeff 8 cookies. then he splits half of the cookies he has left with tod. david let’s c represent the number of cookies that he starts with. he finds the number of cookies that tod has is 1/2 the difference of c and 8. write an expression to represent the number of cookies that tod has.

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?

Nicole is making carrot bread she needs 5 cups of carrots for 2 cups of sugar.what is the ratio of cups of sugar to cups of carrots that nicole will need? write the ration in three different ways