Treatment of the following stereoisomer of 1-bromo-1,2-diphenylpropane with sodium ethoxide in ethanol gives a single stereoisomer of 1,2-diphenylpropene. draw the e2 elimination product of the reaction. take into account that the starting stereochemistry affects the resulting double bond stereochemistry. consider e/z stereochemistry of alkenes. do not show stereochemistry in other cases. you do not have to explicitly draw h atoms. in cases where there is more than one answer, just draw one.