Answer
1- The two phenyl groups will be on the same carbon.
2- Due to the free radical formed on the styrene molecule on the carbon that carry the phenyl group.
Work Step by Step
1- The structure that results from adding the Phenyl radical on the other end of the styrene double bond will have two phenyl rings on the same carbon instead of a phenyl ring on each carbon. And the free radical will be on the other carbon.
2- The polymer has phenyl groups substituted on every
other carbon atom, as the first intermediate has a phenyl group on each carbon, when we add another styrene molecule the double bond cleaved to give a free radical on the carbon that has the phenyl group while the $-CH_{2}-$ Carbon engaged in the chain normally.
