How many possible sandwiches: 4 types of bread & 6 types of cold cuts?

Ricky takes out a $31,800 student loan to pay his expenses while he is in college. after graduation, he will begin making payments of $190.66 per month for the next 30 years to pay off the loan. how much more will ricky end up paying for the loan than the original value of $31,800? ricky will end up paying $ more than he borrowed to pay off the loan.

Ten times the square of a non-zero number is eqaul to ninety times the number

Is it greater than or less than7*3_9*2