Suppose you are working on an optimization problem. Which of the following are true? (Select all that apply.) O In an optimization problem, the final answer MIGHT be found at an endpoint of the domain. O In an optimization problem where you are looking for a maximum, if there is only one critical point then that critical point is always the maximum. O In an optimization problem, the final answer MIGHT be found at a critical point where the derivative is 0. O In an optimization problem, the final answer MIGHT be found at a critical point where the derivative is undefined. O In an optimization problem, the maximum or minimum is ALWAYS located at a critical point where the derivative is 0