The average speed is 0.28
The correct answer is A. Alkali metals.
I hope this helped
A space-filling model shows the relative amount of space each atom takes up. In other words, a space-filling model can show relative sizes of atoms. However, unlike ball-and-stick or structural models, space-filling models do not show bond lengths clearly. Bonds are not really like sticks in a ball-and-stick model.
Hey I tried but could not find your answer, but maybe you could try to calculate the average of bpts of the different elements in the compound to find the boiling point. And when you know the bpt, you can find out whether it is a liquid or gas. But after searching a lot, I found it was a solid. Good luck!
