How can water vapor be detected?
Thermometer radiography A computer satellites Barometer Evaporation Windmills Solar panels
A B C D E F G H
If it's raining AND barometer is steady, then predict rain.
Water vapor can be detected by barometer. 
How can water vapor be detected? (A) Thermometer (B) radiography (C) A computer (D) satellites (E) Barometer (F) Evaporation (G) Windmills (H) Solar panels