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16. Let p(x) = x5 - 3x*+ 2x - 1. Use the Intermediate Value Theorem to show there is a zero. 17. Which of the following functions has neither a local nor global extreme value? Explain. (A)f( x) = Vx (B) f (x) = x (C)f ( x) = x3 (D) f(x) =x* 18.Find the values of a and b that make the function f continuous on (-co, 00). (7x + 5a)3 if x50 f (x) = bx2+8 if0 2 19) A rectangular storage container with an open top is to have a volume of 10 m3. The length of its base is twice the width. Material for the base costs $10 per square meter. Material for the side's costs $6 per square meter. a) Find the dimensions of the container that minimize the cost of materials. b) Find the cost of materials for the cheapest such container. 20) a) Is the function f(x) =- 1 x3+1 differentiable on the open interval (-1,1)? b) Is the function f(x) : 2x x3-9 differentiable on the open interval (-4, 4)