Explanation

Sulfur dioxide (SO₂) and nitrogen dioxide (NO₂) are primary precursors of acid rain.

Acid rain is a consequence of these atmospheric pollutants reacting with water, oxygen, and other chemicals to form acidic compounds. 

These acids contribute to environmental damage.

Explanation

 Bleaching powder is chemically known as calcium oxychloride 

Chemical formula CaOCl₂.

It is used as a disinfectant and bleaching agent.

Explanation

• The Strait of Hormuz is a vital, narrow waterway 
• Located between Iran (north) and Oman/United Arab Emirates (south)
• Separates Iran and Oman
• Link the Persian Gulf to the Gulf of Oman and the Arabian Sea.
• 33 km wide at its narrowest point.

Additional information:

The Strait of Bosporus connects the Black Sea with the Sea of Marmara

Start of Gibraltar connects the Atlantic Ocean to the Mediterranean Sea

Last updated by NS on 20-April-2026

Explanation

A celestial body that revolves around a planet is known as a satellite

Which can be natural (like the Moon) or artificial (like the International Space Station).

A celestial body that revolves around a planet is known as a moon.

Moons are natural satellites orbiting planets and can vary in size and composition.

Explanation

Abraham Lincoln was assassinated on April 15, 1865.

He was the 16th president of the United States from 1861 until his assassination in 1865.

Additional information

• Abraham Lincoln- 1865
• James Garfield- 1881
• William McKinley- 1901
• John F. Kennedy- 1963.
  

Explanation

Israeli Prime Minister Benjamin Netanyahu announced Operation Rising Lion,

This happened on 13 June 2025.

Six nuclear scientists were killed

The Iran–Israel war (13 – 24 June 2025), also known as the Twelve-Day War,

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Explanation

Step-by-step Solution:

Given numbers:

17, 13, 18, 17, 14, 18, 19, 17, 13, 16, 18, 20

1. Arrange in ascending order:

13, 13, 14, 16, 17, 17, 17, 18, 18, 18, 19, 20

2. Count the numbers:

Total = 12 (even number)

3. Median = average of the 6th and 7th terms:

6th term = 17, 7th term = 17

Median = (17 + 17) / 2 = 17

Explanation

Australia's total area is approximately 7.7 million square kilometers (or about 3 million square miles)

In Kilometers: ~7,688,287 km² (2,968,464 sq mi)

It is the sixth-largest country in the world and the largest in Oceania.

Additional information 

Capital is Canberra.

Currency is the Australian Dollar.

Official language is English.

National game is Cricket.

Australia is in Continent Oceania.

Australia Primary Religion is Christianity (But Secular Country).

Parliament called Federal Parliament.

Australia flas has three colours.

Australia's highest-ranking military: Australian Active Service Medal

Explanation

Greenland is within the Kingdom of Denmark.

Geographically part of the North American continent

It is the world's largest island.

  

The capital and largest city is Nuuk.

Area: 2.131 million km²

Explanation

Electrostatic precipitators use static electricity to remove smoke and dust from industrial gases.

Smoke particles are given an electrical charge as they pass through the device.

Charged particles are attracted to oppositely charged plates and stick to them.

This process ensures that the gases released into the atmosphere are cleaner.

Static electricity is widely used in pollution control and air purification system