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Explain using mechanistic arguments why the reaction of 2-bromo-1,2-diphenylpropane (either enantiomer) with sodium ethoxide (NaOEt) in ethanol (EtOH) at 80°C produces mainly (E)-1,2-diphenylpropene [little of the (Z) diastereomer is formed]. Br EtONa EtOH, Δ + Z (major) (minor) The carbocation required for formation of the Z diastereomer is higher in energy because of electron withdrawing inductive effects. O The carbanion required for formation of the Z diastereomer is higher in energy because this transition state has fewer resonance contributors. O The anti coplanar arrangement of atoms leading to the Z diastereomer is higher in energy due to steric effects. O The transition state leading to the Z diastereomer is higher in energy due to angle strain.