Explanation

The stratosphere prevents UV rays from coming surface of the Earth

90% of the ozone in the atmosphere is occupied by the Stratosphere.

Ozone molecules are constantly formed and destroyed in the stratosphere

Additional Information

Ozone is a molecule that contains three oxygen atoms

The atmosphere can be divided into five layers:

1. Troposphere (all weather occurs within this layer)
2. Stratosphere (ozone layer absorbs UV rays)
3. Mesosphere (coldest layer of the atmosphere)
4. Thermosphere (radiowaves transmitted from the Earth and reflected by this layer)
5. Exosphere (molecules and atoms escape)

Explanation

Lead is the metal that pollutes the air of big cities.

Due to the usage of lead petroleum,

when a lead is emitted, it causes damage to air and is a major pollutant.

Explanation

In 1901, the British carved out the northwest portions of Punjab Province to create the Northwest Frontier Province (NWFP)

Lord Curzon separated the area beyond the river Indus of Punjab and formed a new province named North-West Frontier 

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NWFP was renamed "Khyber Pakhtunkhwa" on  19 April 2010 after 18th amendment of the constitution of Pakistan with 90 votes.

NA21-8-2023

Explanation

Mountaineer Sajid Ali Sadpara, son of Late Ali Sadpara, became the first Pakistani to scale the Annapurna mountain without the support of high-altitude porters and supplemental oxygen.

Date: 15 April 2023

Annapurna location: Nepal (world’s 10th highest peak)

Annapurna height: 8091 metre 

Explanation

What is the difference among application, program and software?

Application: A specific software designed to perform a particular task, like word processing or browsing the internet.

Program: A set of instructions written to execute a particular task or solve a problem, which can be part of an application or software.

Software: A broad term that refers to any collection of programs or applications that perform various tasks on a computer system.

Explanation

Cadmium rods are inserted in nuclear reacter to absorb the extra nucleons.

Cadmium has a high thermal neutron absorption cross section.

Therefore, cadmium rods will absorb neutrons, making them unavailable to cause fission.

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Explanation

"His fascination with history compelled him to delve into ancient archives, from uncovering forgotten tales from centuries past."

• Into is used to suggest moving deeply into something (like archives).
• From indicates the source or origin, in this case, the forgotten tales from centuries past.

Explanation

Photon with energy greater than 1.02 MeV can interact with matter as Pair Production.

MeV stands for Mega electron-volt.

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Explanation

"The environments" refers to specific natural settings already known or implied.

Use of "the" is proper when talking about general threats to particular environments.

Explanation

Oghab 44 or Eagle 44 is an Iranian underground airbase unveiled in February 2023.

It is the first tactical and secret airbase for the army's air force

That accommodates the fighters, bombers, and Iranian UAVs.