Explanation

The most abundant gas in the atmosphere is nitrogen, with oxygen second.

Argon, an inert gas, is the third most abundant gas in the atmosphere.

Explanation

Neil Armstrong became the first human to step on the moon.

They did experiments on July 20, 1969.

He walked around for three hours.

Explanation

Explanation

• The freezing point of water is 0°C (zero degrees Centigrade). 
• The boiling point of water on the Centigrade scale (also known as the Celsius scale) 100°C (one hundred degrees Centigrade).

Explanation

The usual gases used for lifting airships are hydrogen and helium.

Hydrogen is the lightest known gas and thus has great lifting capacity,

Helium is not as buoyant but is far safer than hydrogen because it does not burn.

Explanation

Venus is the brightest planet in the Solar System.

Explanation

Bronze is an Alloy consisting primarily of copper, commonly with about 12-12.5% tin .

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RY 23-12-2022

Explanation

علم الحشرات، وہ علم جو حشرات کی ساخت سے تعلق رکھتی ہے

Entomology Insects: کیڑے مکوڑے یا حشرات 

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Entomology is the study of insects and their relationship to humans, the environment, and other organisms.

RK12-12-22

Explanation

Water has maximum density at 4°C.

When Water is in its Solid form (Ice) below 0°C.

Explanation

Mitochondria is known as powerhouse of cell because it serves as site for synthesis of Adenosine Triphosphate (ATP),

the energy currency of cell, through the process of aerobic cellular respiration.

ATP serves as energy currency for different cell activities.

A cell consists of three parts:

1. The cell membrane,

2. The nucleus, and,

3. Between the two, the cytoplasm.