Answer:
Generated by the motion of molten iron in Earth's core, the magnetic field protects our planet from cosmic radiation and from the charged particles emitted by our Sun.
The Northeast became a leader in commerce because of its location and early development of industrial industries. The Northeast became a manufacturing hub in the colonies and in the newly formed United States which created specialization and the growth of commerce in this region relative to the South which was more agriculturally based.
It depends on the mass of the ice,temperature around it and latent heat energy required to melt the ice.
However the furthest a ice berg can travel is estimately 32-40°n/s
