15+55×66÷20%+4 tell me the answer and explain?

Given the following statements, which is the best

What is the value of the expression 9+n/3-6 when n = 12? 1. 5. 7. 12.

Each month, a shopkeeper spends 5x + 14 dollars on rent and electricity. if he spends 3x−5 dollars on rent, how much does he spend on electricity? for which value(s) of x is the amount the shopkeeper spends on electricity less than $100? explain how you found the value(s).