Cirrus clouds are thin, wispy clouds blown by high winds into long streamers. They are considered “high clouds” forming above 6000 m (20,000 ft). Cirrus clouds usually move across the sky from west to east. They generally mean fair to pleasant weather.

Correct Option: A

Cirrus clouds are thin, wispy clouds blown by high winds into long streamers. They are considered “high clouds” forming above 6000 m (20,000 ft). Cirrus clouds usually move across the sky from west to east. They generally mean fair to pleasant weather.

A yardang is a streamlined hill carved from bedrock or any consolidated or semiconsolidated material by the dual action of wind abrasion, dust and sand, and deflation. Yardangs become elongated features typically three or more times longer than wide, and when viewed from above, resemble the hull of a boat.

Correct Option: B

A yardang is a streamlined hill carved from bedrock or any consolidated or semiconsolidated material by the dual action of wind abrasion, dust and sand, and deflation. Yardangs become elongated features typically three or more times longer than wide, and when viewed from above, resemble the hull of a boat.

An isohyet or isohyetal line (from huetos, meaning ‘rain’) is a line joining points of equal precipitation on a map. A map with isohyets is called an isohyetal map.

Correct Option: D

An isohyet or isohyetal line (from huetos, meaning ‘rain’) is a line joining points of equal precipitation on a map. A map with isohyets is called an isohyetal map.

The troposphere is the lowest layer of the Earth’s atmosphere. The air is very well mixed and the temperature decreases with altitude.

Correct Option: A

The troposphere is the lowest layer of the Earth’s atmosphere. The air is very well mixed and the temperature decreases with altitude.