The temperature (in °F) of a greenhouse is recorded continuously over the 12-hour…
MATHEMATICS · Single correct · AP · Calculus AB · Limits and Continuity · Limits and Continuity
Problem
The temperature T(t) (in °F) of a greenhouse is recorded continuously over the 12-hour period from midnight (t=0) to noon (t=12). Measurements show T(0)=60, T(6)=55, and T(12)=80. Which of the following sets of claims is guaranteed to be true?
(a) There exists a time t in (0,12) with T(t)=90.
(b) There exists a single time t in (0,12) with T(t)=70 and T′(t)=0.
(c) There exists a time t1 in (0,6) with T(t1)=58 and a (possibly different) time t2 in (6,12) with T(t2)=70.
(d) The minimum temperature on (0,12) is 55∘F and occurs exactly at t=6.