Someone please help this is the last question of my final.

Kevin has just finished paying off his loan. he was assessed a service charge of $422. he paid off the principal and the interest by making weekly payments of $36.13 for four years. if the principal was $7,150, how much did kevin pay in finance charges, to the nearest dollar? a. $498 b. $365 c. $422 d. $787

Find the greatest common factor of the polynomial: 10x^5+15x^4-25x^3 10x^5 x^3 5x^3 5

Joseph haydn pet store offers wide variety of leashes for dogs. the store purchases one popular type of leash from its manufacturer for $4.38 each. joseph haydn pets marks up leashes at a rate of 238% of cost. what is the retail price of the popular leash?