Evaluate each expression express the result in scientific notation PLSSS I NEED THIS QUICK AND INCLUDE THE EXPLANATION

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

Present age of man is 45 years, 5 years back his age was 4 times age of his son what is present age of his son?

Einstein office equipment has a rental plan for office machines. a fax machine that lists for $722.98 can be rented for 22% of the price annually. the state imposes a usage charge of 3.2%. if stephen hawking travel decides to rent the fax machine, what will its total monthly rental charge be?