Which of the following plants is commonly used as green manure?

The freezing point of a $1.00 \, m$ aqueous solution of $HF$ is $-1.91^o C$. The freezing point depression constant of water $K_f$ is $1.86 \, K \, kg \, mol^{-1}$. The percentage of dissociation of $HF$ at this concentration is ......... $\%$

Which stage of prophase-$I$ is represented in the given figure?

Which of the following reactions is correct?

When two species of different genealogy come to resemble each other as a result of adaptation,the phenomenon is termed as

From a disc of radius $R$ and mass $M$,a circular hole of diameter $R$,whose rim passes through the centre,is cut. What is the moment of inertia of the remaining part of the disc about a perpendicular axis passing through the centre?