Draw the structure of (1e,4r)-1,4-dimethylcyclodecene. higher priority groups the e isomer has two higher priority groups on opposite sides. the z isomer has two on the same side when placing the lowest priority group away from you, the r isomer will have the remaing groups in clockwise order (1e,4r)-1,4-dimethylcyclodecene will have 10 carbon atoms in its parent chain chs groups are located on carbon atoms 1,4.