The benguela current, the peru current, and the california current is what

mass and volume are the answers you are looking for

e/c, where e is its total energy

you can cut your hand off if your not

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.