Gretta was interested in plant growth and conducted an investigation. she planted three groups of indoor plants and used lamps with bright bulbs to learn about the effects of light position on plant growth. she gave all three groups of plants the same amount of water and hours of light per day. the one difference between the three groups was the location of the lamps. for group 1, the lamp was placed directly above the plants; for group 2, to the left of them; and group 3, to the right. she observed and measured the plants’ growth for two weeks. gretta recorded some predictions before beginning her investigation. which of her predictions was supported by her data?