In the Boolean algebra,the expression $\left( {\overline {\bar A \cdot \bar B} } \right) \cdot A$ is equal to:

Input waveforms $A$ and $B$ as shown in Fig-$I$ are applied to the combination of gates as shown in Fig-$II$. Which of the waveforms shown in Fig-$(i)$ to Fig-$(iv)$ correctly represents the output waveform $Y$?

Identify the correct truth table of the given logical circuit.

If three logic gates are connected as shown in the figure,then the correct truth table of the circuit is

The logic gate equivalent to the given logic circuit is

Identify the equivalent logic gate represented by the given circuit.