The well-known romance novelist Celestine A. Lafleur (a.k.a. Bertha Snodgrass) has decided to sell the screen rights to her latest book, Henrietta's Heaving Heart, to Boxoffice Success Productions for $56,000. In addition, the contract ensures Ms. Lafleur royalties of 5% of the net profits. Express her income I as a function of the net profit N. I(N) = Determine the net profit (in dollars) necessary to bring her an income of $130,000. N = $ What is her marginal income (share in dollars of each dollar of net profit)? $ per dollar of net profit