Whats the work for 90 divided by 190?

Based on what i know about mean, this doesn't add up.

Asmall business produces and sells balls. the fixed costs are $20 and each ball costs $4.32 to produce. each ball sells for $8.32. write the equations for the total cost, c, and the revenue, r, then use the graphing method to determine how many balls must be sold to break even.

Over which interval is the graph of f(x) = x2 + 5x + 6 increasing?