Cover it. Heat it. Place it in the dark. Put salt in it.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Water at 20°C in an uncovered pan is evaporating very slowly. What could be done to the water to make it evaporate more quickly?
Possibilities:
- Cover it.
- Heat it.
- Place it in the dark.
- Put salt in it.

Heat it.