A scientist has two identical plants placed by a window. One is in a red pot, and the other is in a yellow pot. She waters the one in the red pot with regular water and the one in the yellow pot with nitrogen-enriched water. After 5 days, she counts the number of flowers on each plant. What was her scientific question?
1. Does the amount of nitrogen affect the number of flowers on a plant?
2. Does sunlight affect the number of flowers on a plant?
3. Does time affect the number of flowers on a plant?
4. Does the color of the pot affect the number of flowers on a plant?