For the function f(x)=8x+1, find f''(x), f''(0), f'(3), and f''(-8). Find f''(x). f'(x)= (Use integers or fractions for any numbers in the expression.) Find f''(0). Select the correct answer below and, if necessary, fill in the answer box to complete your choice. OA. f''(0)=(Simplify your answer.) OB. f''(0) is undefined. Find f''(3). Select the correct answer below and, if necessary, fill in the answer box to complete your choice. OA. f'(3) is undefined. OB. f'(3) (Simplify your answer.) Find f''(-8). Select the correct answer below and, if necessary, fill in the answer box to complete your choice. OA. f'(-8)= (Simplify your answer.)