1. Molecular formula C8H10 is 1, 2 – dicyclopropylethyne
2. 1, 2 – dicyclo propyl ethyne (A) on ozonolysis to give cyclo propyl carboxylic acid (B)
3. Compound C3H5Br is Bromo cyclo propane (C), which on reacts with Mg in dry ether gives Grignard reagent (D) which on treatment with CO2followed by acidification gives cyclo propyl carboxylic acid (B).