1. A prot tax is levied on prots (instead of on sales quantity). If the prots tax is (Mt) and beforetax prots equal (19 (t) C) y (t), after-tax prots equal (1 q) (15)) (p (t) C') y (t). Compare the effects, on a mine owner's incentive to extract, of a constant prots tax (15 and a prots tax q (t) that increases over time