1. The longest coastline in India is along the state of Gujarat. Its length is approximately 1,600 kilometres. This coastline borders the Arabian Sea and includes many beautiful beaches, islands and ports.

2. Gujarat's coastline is important for India's economy and culture. It is an important centre for tourism, fishing and trade. Several important ports are also located on the coastline, such as Mundra, Kandla and Porbandar.

1. During an earthquake, the velocity of the upper part of the waves will increase along with the increase in density which will propel the object passing through it.

2. Earthquake shock When seismic waves occur in a place with soft soil sediments, their propagation increases the natural period, which produces an echo.

All of the following options are correct.

1. Lower the pressure, greater the atmospheric disturbance.

2. Air move from higher to low pressure.

1. Indian black soil is commonly known as black cotton soil or "Regur".

2. Black soil is known as black cotton soil because cotton is an important crop which is grown in this type of soil.

3..Black soil is good for the production of cotton, oilseeds, wheat, linseed, millet and tobacco. This soil is rich in calcium carbonate, potash, lime but has low phosphorus content. Black soils can hold a lot of moisture.

4. It is mostly found in the peninsular plateau of India.

1. Four rivers (Rupangarh, Mentha, Khari, Khandela) fall into Sambhar Lake. Salt is produced on a large scale from this lake.

2. Sambhar Lake: This is a salt water lake located near Jaipur city in Rajasthan state of India. This lake is situated at an altitude of 1,200 feet above sea level.

Damdama is situated in Gurugram, a district in the Indian state of Haryana. Damdama Lake is the Biggest Natural Lake of Haryana.

The first Public Bicycle Sharing (PBS) system in India was launched in 2017 in Mysuru.

A team of four Indian Army personnel successfully climbed Mt Everest without using oxygen cylinders.