Question

Gretchen wants to run a test to discover whether glass, copper, wood, or plastic conduct electricity. She sets up a circuit connecting a battery to a light bulb, with a small gap she will use to test the conductivity of the different substances. One at a time, she connects the circuit with the chosen test material, and records whether or not the light bulb comes on. The variables in this experiment are

Answer 1

The plastic, wood, copper, and glass are the variables. The variables in an experiment are the things we can change and then test.

Answer 2

battery,and i think the light bulb because it depends how much energy the light bulb needs