Please answer the questions below ASAP, make sure they are right as well. I will highly consider giving you thumbs up

Questions:

Question 3 (1 point) If f (x) = x3 (x2 - 56), then fis increasing on which one of the following intervals? O a) (-co, - V/8) U (V8, 00) O b) ( -0o, 0 ) U (18, 00) O c) ( - V8, 0) U (0, V8) O d) (-V8, 0) O e) (0, V8) Question 4 (1 point) Using the first derivative test f (x) = x3 (x2 - 56 ) has local minimum number(s) at O a) V8 O b) 0, V8 O c) - V8 O d) . O e) None of the above Question 5 (1 point) Using the first derivative test f (x) = x3 (x2 - 14) has local maximum number(s) at O a) V2 O b) 0, 2 O c) - V2 O d) co O e) None of the above