The owner of a bookstore developed a model for determining the price of
rare comic books. The price, P, of each book should vary directly with the
number of people, N, that have requested the book and inversely to the
number of such books in existence, M. If N=10 people, M=10,000 copies,
and P = $5, then find P for N = 200 people and M = 100 copies,