Please answer all components.

The polynomial function of least degree with a leading coefficient of 1 is: f(x) = x3 + ax2 + bx + c

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $36.98. find the probability that a randomly selected bill will have an amount greater than $173, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

Is 0.8 a rational or irrational number