B- 8.2980
C- 11.2603
F- 17.4228
Li- 5.3917
Na- 5.1391
I would say your answer is Na.
<span>The student is incorrect because helium has 2 valence electrons and it's in group 18 because the first energy level is full. Although helium is placed in Group 18 which generally has 8 valence electrons, it does not have 8 valence electrons as the student suggested. It was grouped together with the noble gases because it exhibits similar properties with them. </span>
The equilibrium means that amount that are coming equals the amount that are going.
So the correct answers are
<span>2. A person's income and expenses are equal every month.
</span><span>3. The pressure exerted on the inside of a balloon by the gas inside is equal to the pressure exerted on the outside of the balloon by the atmosphere.</span>
Answer:
A and B is the answer as there structure change