Mathematics homework help

 Show all the various steps to arrive at the answer.
Section A
3. For an investment of $100,000 at 9% interest for 3 years, find
(a) the simple  interest, and (b) the compound interest if interest is calculated once per year.
 
4. For an investment of $100,000 at 2% interest for 9 years, find (a) the simple  interest, and (b) the compound interest if interest is calculated once per year
Section B
 
1)As part of his retirement planning, Mr.Martin purchases an annuity that pays  12.5% compounded quarterly. If the quarterly payment is $9,500, how much will Mr. Martin  have saved in 5 years?
2)As part of his retirement planning, Mr. White purchases an annuity that pays  8.5% compounded semiannually. If the semi annual payment is $7000, how much will Mr.  White have saved in 5 years?
 
Section C
1. A house sells for $268,500 and a 40% down payment is made. A 30-year mortgage at 7% was obtained.
(i) Find the down payment.
(ii) Find the amount of the mortgage.
(iii) Find the monthly payment.
(iv) Find the total interest paid