PLease im going to fail do these questions

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.

What is the slope of (0,32) and (100,212)

How many significant figures are there in the number 10.76?