The owner of an apartment building can rent all 50 apartments if she charges $1800 per month, but she rents one fewer apartment for each $60 increase in monthly rent.

(a) Construct a table that gives the revenue generated if she charges $1800, $1860, and $1920.

(b) Does her revenue from the rental of the apartments increase or decrease as she increases the rent from $1800 to $1920?

(c) Write an equation that gives the revenue from rental of the apartments if she makes x increases of $60 in the rent.

(d) Find the rent she should charge to maximize her revenue.