You did an experiment where you want to test if a special kind of fertilizer will actually help your apple tree produce a lot of apples. To do the experiment you went to your local nursery and purchased two of the same kind of apple trees. You planted both trees in your sunny backyard , gave both of them the same amount of waterbut you gave one tree the special fertilizer and the other tree with the regular old fertilizer you've used before . After about a month , you noticed that the tree that got the special fertilizer grew over 100 apples than the other tree that grew about 40 apples . From this experiment , which of the following is considered the dependent variable ?