Vegetative propagation in mint occurs by

Which of the following is a favourable factor for cation formation?

If $A$ and $B$ are any two sets,then $A \cap (A \cup B)$ is equal to

Which of the following is a polyamide?

For a binomial variate $X$ with $n=6$, if $P(X=2)=9 P(X=4)$, then its variance is

Which of the following statements are correct for alkali metal compounds?
$(i)$ Superoxides are paramagnetic in nature.
$(ii)$ The basic strengths of hydroxides increase down the group.
$(iii)$ The conductivity of chlorides in their aqueous solutions decreases down the group.
$(iv)$ The basic nature of carbonates in aqueous solutions is due to cationic hydrolysis.