I had posted this question before and got an answer of 70 months to pay off for part D of the question which is correct but I cannot follow how they got there so i'm hoping someone can answer part D and E below with the steps so I can understand how the math is done

A service may pay off all the loans say $25,000 worth so that the consumer now only has one debt to pay the one to the consolidation service. The difference is that they may now only pay 12% APR(1% a month) so that instead of paying $500 a month (2% of $25,000)to simply pay the interest, they will be able to pay off the loan.

d)How many months will it take to pay off the $25,000 loan at $500 per month at 12% APR compounded monthly?

e)When the loan is paid off, how much interest has gone to the Debt Consolidation Service?