Penny is making pipe cleaner flowers to sell on Etsy for $1 apiece. Penny and her friends become more efficient as they gain practice in flower production. The first 100 flowers cost $1.50 apiece. The next 100 cost $1.25 apiece. The next 100 cost $1.00 apiece. The next 100 cost $0.75 apiece. All the rest cost $0.50 apiece. What is the marginal cost of the 350th flower? What is the marginal profit? If Penny sells 1000 flowers, how much profit does she earn in total?