Those that disputed the flat Earth theory countered the claim by observing that Christopher Columbus was able to sail around the Earth without falling off the edge and later, by presenting satellite imagery taken from space of a spherical Earth. This example demonstrates that

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a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

its c i just checked it