Arrange the following pestidides in the chronological order of their release into the market.
Organophosphates Organochlorides Sodium chlorate
$\quad \text { (A) } \quad\quad\quad\quad\quad\quad\quad \text { (B) } \quad\quad\quad\quad \text { (C) }$
From the following identify the groups that exhibit negative resonance $(-R)$ effect when attached to conjugated system
$$ \begin{array}{ccccc} \text { Formyl } & \text { Amino } & \text { Alkoxy } & \text { Cyano } & \text { Nitro } \\ A & B & C & D & E \end{array} $$
The diffraction pattern of crystalline solid gave a peak at $20=60^{\circ}$. What is the distance ( in cm ) between the layers which gave this peak?
( $\lambda$ of $X$-rays is $1.54 \mathring{A}$ ) $\left(\sin 30^{\circ}=0.5, \sin 60^{\circ}=0.866 ; n=1\right)$
(a) $8.89 \times 10^{-8}$