An unknown organic compound contains carbon, hydrogen, and bromine only. The mass percentages of C and H are 12.77% C and 1.60% H. Bromine from 1.87 g of this compound has been completely converted into 3.70 g of AgBr. The molar mass of unknown organic compound is 188 u. Determine the molecular formula of the unknown.
◦ CH3Br
◦ C2H3Br2
◦ C2H2Br2
◦ C2H2Br4
◦ C4H6Br4