I need answer it’s geometry
I need the answers please help me you math people

Barbara deposited $300 in the bank. if the bank pays her simple interest at the rate of 4 percent per year, how much money will she have in her account at the end of 9 months?

Which best explains why this triangle is or is not a right triangle ?

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?