Answer:
The principal quantum number of the valence orbitals increases.
Explanation:
The atomic radius of main-group elements generally increases down a group because the principal quantum number of the valence orbitals increases.
In a longitudinal wave, the motion of the medium is parrellel to the direction of the wave.
Newton's first law of motion is often stated as
<span>An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. Therefore, the answer here is A) Newton's First Law.
Hope this helped ;)
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