On a scale from [i to 1, the effectiveness E of a painkilling dmg t hours after entering the bloodstream is displayed in the AE accompanying gure. Complete parts (a) and (b) below. 1 l]. 0.6 114 0.2 p D123456T39111 {:2- A. Nothing can be said about the derivative at those times. "'21- B. The derivative is less than zero. ("22- C. The derivative is zero. 3 D. The derivative is greater than zero. [b] At what time would you estimate that the dmg reaches its maximum effectiveness? t= :| (Type an integer or a decimal.)