Please help me
i don't know this

How to use order of operation in 20 divide by 4 multiply 5 = 1

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.

2.5 milligrams is equivalent to how many grams