ask mattrab

Yes, if the angle between the two vectors is more than 90^o but less than 270⁰. (cosΘ is negative)

SinceECu2+/CuECu2+/Cuhas a greater positive value thanEH+/HEH+/H, the reaction that is feasible at the cathode is

Cu2+(aq)+2eCu(s)

Makar disclosed that he had killed the merchant because he realized his mistake and Aksionov's suffering and now he wanted to make Aksionov release from the prison.

Yes, a vector which has zero magnitude is also a vector in case of two vectors travelling in opposite directions with equal magnitudes. At this case, the resultant vector has zero magnitude but it is still a vector. We call it a null vector.