Which of the following is a natural polymer?

Which of the following pairs of ions have the same paramagnetic moment?

Product $(A)$ is

In an experiment with $15$ observations on $x$,the following results were available: $\sum x^2 = 2830$ and $\sum x = 170$. One observation that was $20$ was found to be wrong and was replaced by the correct value $30$. Then the corrected variance is:

Which one among the following is likely to have the highest levels of $DDT$ depositions in its body?

An increase in equivalent conductance of a strong electrolyte with dilution is mainly due to