Structure Of Atom

Seismographs are instruments used to record the motion of the ground during an earthquake. They are installed in the ground throughout the world and operated as part of a seismographic network.

Koppen's classification is one of the most widely used climate classification systems. It categorizes the world's climate based on the average temperature and precipitation. Developed by Wladimir Koppen in the Early 20th century.

The mesopause is the boundary layer between the mesosphere and the thermosphere in the Earth's atmosphere. It is the region where the lowest temperatures in the Earth's atmosphere are found, typically around -90°C (-130°F).This layer is located at an altitude of about 85-100 kilometers (53-62 miles) above the Earth's surface. The low temperatures are due to the decrease in atmospheric pressure and the limited absorption of solar radiation at these altitudes.

Dhaka is the capital city of Bangladesh, in southern Asia. Set beside the Buriganga River, it is at the center of national government, trade and culture. The 17th-century old city was the Mughal capital of Bengal, and many palaces and mosques remain.