Find the sum of 2x^2 + 3x - 4, 8 - 3x, and -5x^2 + 2

me i'm so confused

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?

Ebuka's monthly rent is $750. if ebuka pays the rent late, his landlord charges 4% interest per week that the payment is late. write a function that gives the total cost r(t), in dollars, of ebuka's rent if he pays it t weeks late.

Asequence is a function whose is the set of natural numbers