Work done in increasing the size of a soap bubble from a radius of $3\, cm$ to $5\, cm$ is nearly (Surface tension of soap solution $= 0.03\, Nm^{-1}$). (in $\pi \,mJ$)

One mole of $A_{(g)}$ is heated to $200^{\circ} C$ in a one litre closed flask,till the following equilibrium is reached.
$A_{(g)} \rightleftharpoons B_{(g)}$
The rate of forward reaction at equilibrium is $0.02 \ mol \ L^{-1} \ min^{-1}$. What is the rate (in $mol \ L^{-1} \ min^{-1}$) of the backward reaction at equilibrium?

Match Column-$I$ with Column-$II$ and select the correct option.

Column-$I$	Column-$II$
$A$. Fishes	$(i)$. Three-chambered heart
$B$. Amphibians	$(ii)$. Incomplete double circulation
$C$. Birds	$(iii)$. Four-chambered heart
	$(iv)$. Single circulation
	$(v)$. Two-chambered heart
	$(vi)$. Double circulation

Which of the following is an accessory whorl of a flower?

Which one of the taxonomic aids can give comprehensive account of complete compiled information of any one genus or family at a particular time?

Which insect is used to control the spread of prickly pear cactus $(Opuntia)$?