Detailed Video Solution: Video Solution (Click HERE)
$\text{R-3, S-1}$ Detailed Explanation Here: https://www.youtube.com/watch?v=-30dUjh6Qv4
$P-4$ by De-Morgan’s Law ( $\overline{A +B} = \overline{A}.\overline{B} $ )
$Q-2$ by De-Morgan’s Law ( $\overline{A.B} = \overline{A} + \overline{B} $ )
NOTE that: $A’ \oplus B = A \odot B$ ; Also $\overline{A \odot B} = A \oplus B$
$S-1 $ by the following equivalence: $A \odot B = A’ \oplus B $
$R-3 $ by the following equivalence: $A \oplus B = \overline{A’ \oplus B} $
$\text{R-3, S-1}$ Detailed Explanation HERE.