To find the inequality that represents how long the dehumidifier can run before it becomes full, we need to consider that the dehumidifier removes 1.6 pints of water every hour and has a maximum capacity of 40 pints.
Let \( h \) represent the number of hours the dehumidifier runs. The amount of water removed by the dehumidifier after \( h \) hours is \( 1.6h \) pints. We want to find out when this amount is less than or equal to the maximum capacity of the dehumidifier (40 pints).
Thus, the correct inequality is:
\[ 1.6h \leq 40 \]
This matches Option #2.
So the answer is Option #2.