IIM Bangalore (UGAT) (QA) PYQs

A bag consists of tokens whose labels are selected from all of the first $n$ even natural numbers. The frequency of each label equals half the label itself. Then the variance of all the labels the bag is

We have a bag of tokens. Each token has a label $m$ chosen from the squares of the first $n$ natural numbers, with frequency $\sqrt{m}$. What is the arithmetic mean of the labels?