A I think I could be wrong I’m not good at this
The balanced equation is:

Then proceed with the following equations.

The answer is

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Its magnifying power is: 4X 5X 9X 20X. A 4-inch, f/5 telescope has a 1-inch eyepiece focal. Its magnifying power is 9x. This answer has been confirmed as correct and helpful.
Answer:
In first shell 2 electrons are present and 7 electrons are present in last shell
Explanation: