QUESTION 14 0.1 points Save Answer Questions 14-16 relate to the following function: f(x) = 10x2 -5x + 20. What is the derivative, or the slope of the tangent line, at X = 5, i.e. f'(5)? 20 X - 5 20-5 QUESTION 15 0.1 points Save Answer What is the derivative, or the slope of the tangent line, at X = 15, i.e. f'(15)? QUESTION 16 0.1 points Save Answer Why is the slope of the function larger at X = 15 than it is at X = 5? Select all the correct answers. (There is more than one.) The derivative function, f(X), is an upward sloping line. The derivative function, f'(X), is a downward sloping line. The original function, f(x), is a U-shaped parabola and it becomes steeper as X increases beyond the turning point at X = - 4 The original function, f(X), is a U-shaped parabola and it becomes steeper as X increases beyond the turning point at X =