Find each of the following:

**A.**

**B.**

**C.**
The interval (with endpoints given to the nearest 0.25) where

interval =

*(Give your answer as an interval or a list of intervals,
e.g.,* **(-infinity,8]** *or*
**(1,5),(7,10)**, *or enter*
**none*** for no intervals.)*

**D.**
The value of