I really need help on these

What could explain what happened when the time was equal to 120 minutes

Average acceleration: i have no idea how to do this.

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.