Reaction : 1 CH₃–CH₂–CH₂–CH₂–CH₃ $\underset{\mathrm{h\nu }}{\stackrel{{\mathrm{Cl}}_2}{\to }}$ Optically active monochloro product(s) are (R)

Reaction : 4 2-methoxy propane $\underset{\mathrm{h\nu }}{\stackrel{{\mathrm{Cl}}_2}{\to }}$ Optically active mono chloro product(s) are (Q)
Sum of P + Q + R + S is