HELP ASAP! 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 Is this a good experimental design? Answer choices: Yes, because all of the materials gave the results she predicted No, Since we dont know the results No, because she is testing to many things Yes, Because she is only changing one piece of experiment