Explanation

Solder is an alloy of  Lead and tin  

An alloy is a mixture of chemical elements of which at least one is a metal. 

Explanation

Tritium is an isotope of hydrogen that is composed of one proton, two neutrons, and one electron.

The symbol for tritium is 3^H.

The atomic number of tritium is 1 

the atomic mass of tritium is 3.

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

The density of ice is 0.9168 g/cm 3.

The density of water is 1 g/cm 3

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

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 admixtures slow down the initial rate of hydration of cement or prolong the setting of cement paste in concrete.

Retarding admixtures are frequently required in hot weather conditions to facilitate delaying the setting time

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Explanation

The third edition of the popular Structural and Stress Analysis provides the reader with a comprehensive introduction to all types of structural and stress analysis.

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Explanation

The center of gravity of an object is where we can consider all of the weight of the object to be concentrated.

This is a useful concept in physics and engineering.

Explanation

Water conservation is the practice of using water efficiently to reduce waste and preserve this precious resource.

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