Enter a T or an F in each answer space below to indicate whether the corresponding statement is true or false.

A good technique is to think of several examples, especially examples which might show that the statement is false!

1. Every continuous function on the interval $( -3, 1 ]$ must have both a maximum and a minimum.
2. Every differentiable function on the interval $( -3,0 ]$ must have both a maximum and a minimum.
3. Every function on the interval $[ -3,0 ]$ must have both a maximum and a minimum.
4. Every function on the interval $( -3,1 ]$ must have both a maximum and a minimum.