The demand function for the Luminar desk lamp is given by p = A(x) = -0.1x2- 0.3x + 39 where x is the quantity demanded in thousands and p is the unit price in dollars. (a) Find F'(xx). F ( x ) = (b) What is the rate of change of the unit price (in dollars per 1,000 lamps) when the quantity demanded is 11,000 units (x = 11)? $ per 1,000 lamps What is the unit price (in dollars) at that level of demand? $