Zero order half life
Changing the concentration of B has no effect on the results.

This statement could only mean one thing: B does not participate in the reaction. Obviously, if B does participate in the reaction, and you change the concentration of B to 0 the reaction won't happen.

The equation for the half life of a zero order reactant is
[Binital]2k.

Zero order reaction have no half-life. Only 1st order reaction has half-life.