A sledgehammer hits a wall How do the hammer and the wall act on each other?

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gans

explanation:

vestigial organs (like your appendix) are organs that no longer serve a purpose.

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.