Which of these are linear functions?

You have 6 dollars +12 pennies +to quarters + 4 dimes=2 nickels how much do you have

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

What is the quotient of m^6/5 ÷ 5/m^2? assume m does not equal pl