A cosmetic company is planning the introduction and promotion of a new lipstick line. The marketing research department, after test marketing the new line in a carefully selected large city, found that the demand in that city is given approximately by p=10−x 0≤x≤2, where x thousand lipsticks were sold per week at a price of $ each.
Find the rate of change of price with respect to demand when weekly demand is 800 lipsticks and interpret the result