NOTE: I realize this is more than one question. I wanted to keep the questions together since the inquiry seems to build upon the previous answer. If Chegg wants to "charge" me for the extra, that is fine.

Vivian wants to buy a house. The house she wants is listed for $300,000, and she wants to avoid PMI insurance. She can get a fixed rate mortgage at 4.25% for 30 years.

What down payment will she need?

If Vivian makes her down payment and takes out the loan described, what will be her monthly payment?

If Vivian makes her down payment and takes out the loan described, what will be the total cost of the house?

What would be the total cost of the house if she took out a 15 year mortgage at 3.125%?

What if Vivian can only pay a 10% down payment, what would her monthly payment be for the 30 year mortgage at 4.25%? (For this example the PMI insurance cost is 1% of the loan amount per year.)