Radha takes some blue solution in a test tube and then puts some drops of lemon juice into it. She leaves the solution for an hour. After she comes back, she looks at the solution and concludes that a chemical change has happened in it. What might have occurred for her to conclude this? * (1 Point)

1.The solution evaporated from the test tube.

2.The drops of lemon juice formed a layer on the solution.

3.The solution changed colour from blue to red.

4.The drops of lemon juice increased the weight of the solution.​