What is the value of expression 3($28+$32)-$10

Nick estimated that 5/8+4/7 is about 2.explain how you know his estimate is not reasonable plz and fast i will give 50 points

The amount of money, in dollars, in an account after t years is given by a = 1000(1.03)^t. the initial deposit into the account was $_^a0 and the interest rate was _a1% per year. only enter numbers in the boxes. do not include any commas or decimal points^t. the initial deposit into the account was $__^a0 and the interest rate is % per year.

Can someone me out here and the tell me the greatest common factor