Which of the following octahedral complexes does not exhibit geometric isomerism? ($A$ and $B$ are monodentate ligands.)

With increasing principal quantum number,the energy difference between adjacent energy levels in $H$ atom

Lenz's law is a consequence of the law of conservation of

Two fair dice are rolled. The probability of the sum of digits on their faces being greater than or equal to $10$ is

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?

The $pK_a$ of a weak acid is $4.8$. What should be the ratio of $\frac{[\text{acid}]}{[\text{salt}]}$,if a buffer of $pH=5.8$ is required?