1) which equipment is used to measure the distance a) light meter b) ruler c) flash light d) measuring tap 2) which is natural source of light a) phone b) led c) bulb d) sun 3) which one is the natural form of energy? a) moon b) sound energy c) fire works d) mirror 4) how light travels a) swinging b) flying c) zigzag d) straight lines 5) what is the artficial light source a) sun b) tv c) stars d) fire 6) what is the name of a bright that is not a light source a) sun b) liggtning c) moon d) stars

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