It is scalar quantityValue of mass not depends on gravitymass of a body is given by here symbol have their usual meaning. mass can never be zero. Option (3) is correct. Because the "" here is relativistic mass and is rest mass. This equation tells about the relativistic mass change when an object travels at a very high speed. Hence this is incorrect about the mass. Also mass is a scalar quantity and it can not be zero, because according to law f conservation od mass, Mass can neither be created nor destroyed.