Some reactions of $NO _2$ relevant to photochemical smog formation are

Identify $A , B , X$ and $Y$
In the system shown below, $x(t)=\sin(t)u(t)$. In steady-state, the response $y(t)$ will be 
The time constant of the network shown in the figure is 
The parallel RLC circuit shown in the figure is in resonance. In this circuit, 
There is a number of factors that contribute to the pollution of the environment. Some of the major causes of atmospheric pollution are given below -