आणविक सूत्र C6H3ClBrI वाले त्रि-प्रतिस्थापित (trisubstituted) बेंजीन व्युत्पन्न के लिए संभावित बेंजीनॉइड समावयवियों (isomers) की कुल संख्या की गणना कीजिए।

Given below are four compounds: (a) n-propyl chloride (b) iso-propyl chloride (c) sec-butyl chloride (d) neo-pentyl chloride The mass percentage of carbon in the compound which exhibits optical isomerism is approximately: (Atomic mass: C=12, H=1, Cl=35.5)

Identify the correct statements from the following: A. Propanal and propanone are functional isomers. B. Ethoxyethane and methoxypropane are metamers. C. But-2-ene shows optical isomerism. D. But-1-ene and but-2-ene are functional isomers. E. Pentane and 2,2-dimethylpropane are chain isomers. Choose the correct answer from the options given below: