Who divided the $Angiosperms$ into two classes?

Which of the following is the correct increasing order of ionic character?

$A$ bullet fired into a fixed target loses half of its velocity after penetrating $3 \ cm$. How much further will it penetrate before coming to rest,assuming that it faces constant resistance to motion? (in $cm$)

At $25^{\circ} C$,the molar conductances at infinite dilution for the strong electrolytes $NaOH$,$NaCl$ and $BaCl_2$ are $248 \times 10^{-4}$,$126 \times 10^{-4}$ and $280 \times 10^{-4} \ S \ m^2 \ mol^{-1}$ respectively. The value of $\lambda_m^{\circ} Ba(OH)_2$ in $S \ m^2 \ mol^{-1}$ is:

Which of the following relations is true?

Which one of the following pesticides is banned now-a-days?