Please help me quick!!

What is the solution to this system of equations?
y=x-20
x+y=84

A. (20,0)
B. (52,32)
C. (50.30)
D. (40,44)

If n stands for number sold and c stands for cost per item, in which column would you use the formula: ? a. column d c. column f b. column e d. column g

Let f(x)=2x and g(x)=2x. graph the functions on the same coordinate plane. what are the solutions to the equation f(x)=g(x) ?me asap

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?