The relative humidity when a dry bulb reads 12 degrees celsius and a wet bulb reads 7 degrees celsius is

48%

Explanation:

The relative humidity can be determined using a dry bulb and a wet bulb. The wet bulb temperature is usually lower than the dry bulb temperature. Hence, to determine the relative humidity, the wet bulb temperature is subtracted from the dry bulb temperature to determine the difference. Then the relative humidity is now determined using this difference and the dry bulb temperature.

Difference between dry bulb temperature and wet bulb temperature = 12°C - 7°C = 5°C

We locate the difference of 5 at a with a dry bulb temperature of 12°C on the table to get:

Relative humidity = 48%

polar areas, such as antarctica or the south pole.