PLEASE HELP

Only need help with 7!

When i add money am i supposed to make it like this 7+12 or 7.00+12.00 because i got 19 dollars for my answer

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

Mr. and mrs. wallace have decided to buy a car for $21,600. they finance $15,000 of it with a 5-year auto loan at 2.9% arp. what will be their monthly payment be? a. $268.20 b. $268.86 c. $269.54 d. $387.16 i need !