"two pieces of iron attract eachother. how can you tell whether they are both magnets?"

A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, cobalt, etc. and attracts or repels other magnets.

If two metal, say iron , attract each other it shows a magnetic pull. Also metal can attract other metal only if it has magnetic fields. Remember to note that the metal should attract Ferromagnetic materials only.

Explanation:

radiation

explanation:

heat is transmitted by radiation

it would be c. predictability