PLEASE ASAP NO LINKS WILL BE REPORTED IF THERE IS Xavier is testing different types of planting soil to determine which type is most effective in growing blueberry bushes. He purchases two different brands of planting soil from a local store. Xavier applies Brand A to an area of the yard that receives full sunlight and Brand B to another area of the yard that is in partial sunlight. He waters the area with Brand B daily; he waters the area with Brand A every other day. At the end of the study, Xavier concludes Brand A is more effective in growing blueberry bushes. Why is his conclusion not valid?