Need a bit of help on this

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).

Olga used 100 ounces of flour to make 225 muffins. how many ounces of flour will be used to make 300 muffins?

What is coefficient of the term of degree of degree 5 in the polynomial below