1) Which one of the following has a negative charge? a) protons b) electrons c) neutrons 2) Which one is an insulator? a) glass b) steel c) copper 3) Which one is a conductor? a) rubber b) wood c) silver 4) Lightning is an example of a) static electricity b) current electricity c) sound energy 5) More vibrations per second produce a) noise b) high sound c) silence 6) is the a) kidneys b) pancreas c) liver 7) which artery supplies blood to the heart muscle? a) aorta b) coronary artery c) pulmonary artery

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