Which of the following is not a lateral meristem?

$A$ bar of cross-sectional area $A$ is subjected to two equal and opposite tensile forces at its ends as shown in the figure. Consider a plane $BB'$ making an angle $\theta$ with the length. The ratio of tensile stress to the shearing stress on the plane $BB'$ is

Identify the blank spaces $a, b, c$ and $d$ given in the following table and select the correct answer.
| Organism | Type | Product |
| :--- | :--- | :--- |
| $a$ | $b$ | Cyclosporin-$A$ |
| $c$ | Bacterium | Butyric acid |
| $d$ | Bacterium | Lactic acid |

Which of the following compounds will be most easily attacked by an electrophile?

The presence of a nitro group in a benzene ring.....

The electrons identified by quantum numbers $n$ and $l$: $(i)$ $n = 4, l = 1$; $(ii)$ $n = 4, l = 0$; $(iii)$ $n = 3, l = 2$; $(iv)$ $n = 3, l = 1$ can be placed in order of increasing energy from the lowest to highest,as