What is 8x2/3 as a mixed number

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

Explain how you can use the associative property to evaluate (7x50)x4.

Is this a polynomial function? i need to know asap