The oxidation states of $S$ atoms in Caro's and Marshall's acids are

In biennial plants,normally the number of carpels is:

The value of $\cos^{-1}\left(\cos\frac{5\pi}{3}\right) + \sin^{-1}\left(\cos\frac{5\pi}{3}\right)$ is

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$ :
Assertion $A$: Size of $Bk^{3+}$ ion is less than $Np^{3+}$ ion.
Reason $R$: The above is a consequence of the actinoid contraction.
In the light of the above statements,choose the correct answer from the options given below:

If $\frac{e^x + 2}{(e^x - 1)(2e^x - 3)} = -\frac{3}{e^x - 1} + \frac{B}{2e^x - 3}$,then $B = $

Which of the following plants are used as green manure in crop fields and sandy soils?