A businessman models the number of items (in thousands) that his company sold from 1998 through 2006 as N(x) = −0.1x3 + x2 − 2x + 9 and the average price per item (in dollars) as P(x) = 0.3x + 7, where x represents the number of years since 1998. Enter a polynomial R(x) that can be used to model the total revenue for this company.