What is $Z$ in the following reaction sequence?
$C_6H_5NH_2$ $\xrightarrow[(i) NaNO_2 + HCl / 273 \ K]{(ii) H_3PO_2 + H_2O}$ $\xrightarrow[(iii) CO, HCl, \text{anhydrous } AlCl_3/CuCl]{} Z$

When a capacitor is connected in series $LR$ circuit,the alternating current flowing in the circuit

The collector plate in an experiment on the photoelectric effect is kept vertically above the emitter plate. $A$ light source is turned on,and a saturation photocurrent is recorded. An electric field is then switched on,which has a vertically downward direction.

Which type of chromosome is shown in the figure below?

The $V-I$ graph for a conductor at temperatures $T_1$ and $T_2$ is as shown in the figure. Then $(T_2 - T_1)$ is proportional to