Mark sells hand-made jewelry at craft shows. He averages 40% gross margin on his jewelry (the price-costs/price is 40%). To register as a vendor, drive, feed himself at a show, and stay the night somewhere averages $400 per show.

a: how much in dollars does mark have to sell at the average show to break even?

b: if mark wants to make $1,000 per show (profit per show) how much does he have to sell (in dollars)?