Will give BRAINLIEST

Bob is putting books on a shelf and takes a break after filling 18 1/2 inches on the book shelf. the book shelf is now 2/3 full. how long is the entire bookshelf?

1) you deposit $2,500 in an account that earns 4% simple interest. how much do you earn in eight years?

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25