Compare and contrast two different measures of humidity

Humidity is measured in two ways; absolute and relative humidity. 

Absolute humidity and Relative humidity both measure the amount of vapor in the air. However, absolute humidity  refers to the measure of the water vapor in the air, despite the temperature of the area. When you talk about Relative humidity, as the name suggests measures the amount of vapor relative to the temperature of the area. 

Iam pretty sure it is c. 2000 bce

Answerdistinguish between the mercalli scale and the richter scale;