Astudent hypothesizes that since elements in the same row have the same number of energy levels they should behave the same in chemical reactions explain why you agree or disagree

 The student is WRONG. Elements that are similar in chemical nature have the same number of outermost electrons not energy level. When taking part in chemical reactions elements may behave similarly. The major reason for their similar behaviour is in the similar number of electrons which they have in their outer most shell. 

The answer is 4 i don't know if its right let me see.

Hbr dissociates to form h+ and br-ca(oh)2 dissociates to form ca2+ and 2oh-the h+ and oh- react to form waterassuming the reactants are dissolved in water, the net reaction is h+ + oh- —> h2oif you’re asked to show all components of the reaction, the complete reaction is 2hbr + ca(oh)2 —> cabr2 + 2h2o