If f(x) = 3x5x + 18, evaluate lim h0 f(3+h)-f(3) h If an answer does not exist, enter DNE. Consider the function f(x)=x-18x Determine the number of points on the graph of y = f(x) that have a horizontal tangent line. In other words, determine the number of solutions to f'(x) = 0. 3 Determine the values of x at which f(x) has a horizontal tangent line. Enter your answer as a comma-separated list of values. The order of the values does not matter. Enter DNE if f(x) does not have any horizontal tangent lines. x 0, 81, 81 -