Answer:
the first line
Explanation:
A rarefaction is a region in a longitudinal wave where the particles are furthest apart. ... The region where the medium is compressed is known as a compression and the region where the medium is spread out is known as a rarefaction.
use this picture as a reference:
<u><em>on the basis of the reaction of heat in plastic , their are two types of plastics : </em></u>
<h2><u>
<em>Thermoplastic & Thermosetting plastics </em></u></h2>
<u><em>Thermoplastics : Plastics which easily get deformed (become soft )on heating and also get bend easily are known as thermoplastics . </em></u>
<u><em>examples : polythene , polyvinyl chloride and polystyrene .</em></u>
<u><em>thermosetting plastics : plastics which once moulded into a shape do not become soft on heating and cannot be moulded again are called thermosetting plastics .</em></u>
<u><em>examples : bakelite , melamine and formica</em></u>
A should be the correct answer because any argument based on science makes a result more logical.
Answer:
beta
Explanation:
A beta particle (symbol β) is a high-speed and high-energy electron which is emitted by radioactive decay of the atomic nucleus during process of the beta decay.
Strontium-90 is material which is most commonly used to produce the beta particles.
Beta particles are used to treat conditions such as eye as well as bone cancer.
The isotopes 55Fe and 58Fe are both Iron, but have a different atomic mass due to the added number of neutrons. Both isotopes have 26 protons, but 55Fe has more neutrons.