Hi aspirant,

A graduation is a marking used to indicate points on a visual scale, which can be present on a container, a measuring device, or the axes of a line plot, usually one of many along a line or curve, each in the form of short line segments perpendicular to the line or curve.

Reading a barometer is simple if you know what different atmospheric pressure values indicate.

1. Rising or steady pressure indicates clearing and cooler weather.
2. Slowly falling pressure indicates rain.
3. Rapidly falling pressure indicates a storm is coming.

Thank You.