Two trains 'A' and 'B' of length '$$l$$' and '$$4 l$$' are travelling into a tunnel of length '$$\mathrm{L}$$' in parallel tracks from opposite directions with velocities $$108 \mathrm{~km} / \mathrm{h}$$ and $$72 \mathrm{~km} / \mathrm{h}$$, respectively. If train 'A' takes $$35 \mathrm{~s}$$ less time than train 'B' to cross the tunnel then. length '$$L$$' of tunnel is :

(Given $$\mathrm{L}=60 l$$ )

Which of the following Maxwell's equation is valid for time varying conditions but not valid for static conditions :

Different combination of 3 resistors of equal resistance $$\mathrm{R}$$ are shown in the figures. The increasing order for power dissipation is:

For the following circuit and given inputs A and B, choose the correct option for output '$$Y$$'