please explain the steps and formulas.

Having just graduated from College with a degree in finance, you landed a job as a finance counselor for a large company. Your very first client is a young couple who want to put their financial business in order. Both the husband and the wife are 27 years ago and in stable employment. They want to retire together at the age of 65. Thus, they have 38 (=65-27) years until retirement from now. They want you to help them in their financial planning by answering a series of questions as follows. 1. The couple plan to buy a house, and the loan amount is $200,000. The annual rate is 5%, and the term is 30 years. How much should they pay for their monthly mortgage? How much interest will they pay for the second month? (hint: monthly interest=monthly interest rate beginning balance of the principal) 2. The couple plan to buy a new car in five years, and start to save money and deposit $300 in their saving account at the end of every month, if the annual rate is 6%, how much will they have at the end of year 5? 3. The couple plan to have their own business in four years, and they plan to invest $5000 in year 1, $6000 in year 2, $8000 in year 3, and $10,000 in year 4, if the annual rate is 5%, how much money will they have at the end of year