How do i do this and how do i anserw it

Abbey purchased a house using a fixed rate mortgage. the annual interest rate is 4.2% compounded monthly for 20 years. the mortgage amount is $235,000. what is the monthly payment on the mortgage? this isn't a multiple choice question have to show my work

Collin did the work to see if 10 is a solution to the equation r/4=2.4

Why is it so easy to buy on impulse and overspend with a credit card? what could you do to counteract this tendency?