Going through eco review problems for my test coming up and had a few questions, any help would be greatly appreciated!

All firms in competitive industry have:
total costs
C = 2q2 + 200
Demand D = 240 ! 3P
Provide labelled diagrams that show how The Firm and The Industry would respond to the introduction of a $20 per unit tax
Would the amount of price increase experienced by consumers be larger if this was an increasing costs industry?

I know how to do the first part of the question, but it's the Increasing Costs Industry part I don't understand.

Thanks!