Answer:

Explanation:
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In this case, given that frequency of the electromagnetic radiation showing off a wavelength of 1.25 m is computed by using the speed of light as shown below:

We plug in the wavelength and speed of light to obtain:

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Answer:
19 protons, 20 neutrons and 18 electrons.
Explanation:
Answer:
This is
1 mole = 18 gram = 6×10^23 molecules
1 gram = ?
1 gram= 18/6×10^23 atoms
1 gram =3×10^-23 atoms