No need explanation   Farmer Josie owns and operates an apple...

No need explanation 

Farmer Josie owns and operates an apple orchard in Upstate New York, and she wants to know if a newly-released fertilizer called Applejack will increase her apple yield. She acquires a bottle of Applejack and a bottle of the fertilizer that she currently uses. She designs an experiment to test the following research question:

Will trees sprayed with Applejack yield more apples over the course of one growing season as compared to trees sprayed with the fertilizer that she currently uses?

1. What are two predictions that could be made based on this research question?

Both fertilizers have to be mixed with the same dissolving solution before they can be applied, so Josie decides to include three treatment groups in her experiment. To one group she'll apply Applejack mixed with the dissolving solution; to another group she'll apply her current fertilizer mixed with the dissolving solution; and to a third group she'll apply just the dissolving solution without any fertilizer.

Generally, these three types of treatment groups are defined as:

1. experimental (includes the variable being tested)
2. negative control (excludes the variable being tested)
3. positive control (includes a different variable with a known effect)

Which of Josie's treatment groups is the experimental group? Which is the negative control? Which is the positive control?