Explanation:
( a )
<u>The four types of spread spectrum techniques are as follows -</u>
1. Direct sequence spread spectrum .
2. frequency hopping spread spectrum .
3. chirp spread spectrum .
4. time hopping spread spectrum .
( b )
<u>The Direct sequence spread spectrum was devised for eavesdropping in the military .</u>
In the field of telecommunications , the Direct sequence spread spectrum , it is the technique of spread spectrum modulation which is used to reduce the overall inference of the signal .
For any element the nucleus consists of neutrons and protons while electrons orbit around the nucleus, (3)
I forgot what quantum means to be honest, the Bohr model In atomic physics, the Bohr model or Rutherford–Bohr model, presented by Niels Bohr and Ernest Rutherford in 1913, is a system consisting of a small, dense nucleus surrounded by orbiting electrons—similar to the structure of the Solar System, but with attraction provided by electrostatic forces in place of gravity. After the cubical model (1902), the plum pudding model (1904), the Saturnian model (1904), and the Rutherford model (1911) came the Rutherford–Bohr model or just Bohr model for short (1913). The improvement over the 1911 Rutherford model mainly concerned the new quantum physical interpretation.
A fusion reaction can be regarded as the type of reaction that occurs where two lighter elements come together in a type of reaction giving rise to a heavier/more massive element.
A fusion reaction always creates a more massive atomic nucleus (option c).
When the two lighter nuclei comes together in a reaction, a more heavier/massive nucleus is formed but its mass will still be less than the combined mass of the two reactant nuclei.
This also indicates that the left over mass may have been released as energy.
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