Draw the major elimination product for the reaction. There is a scheme of a reaction, where the reactant is CH3CH2CHCH3, with a Br atom attached to the third carbon atom (from left to right). The reagent is CH3O minus in DMSO.

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

the answer is barium and copper bromide

i believe the answer is three water molecules