A Dehumidifier Is Used to Reduce the Moisture in a Basement

Multiple Choice

A dehumidifier is used to reduce the moisture in a basement. The level of moisture reported on the display panel when the dehumidifier is turned on is 70%. The percent moisture, P(t) , at time t is recorded for different times t in the table. $$\begin{array} { l l l l l l l } T & 0 & 2 & 6 & 15 & 20 & 30 \\P ( t ) & 70 & 67 & 60 & 53 & 51 & 50\end{array}$$ Estimate P'(20) .

A) -0.20% per minute
B) -0.10% per minute
C) 0.10% per minute
D) 0.20% per minute
E) 0.40% per minute