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3 Question 5 10 pts An environmental scientist is interested in the erosion effect of the pH level of rainwater on soil. She prepares 4 large plots, each with a unique soil composition. She splits each plot into a 5x5 grid ['25 sub-plots in each plot] and then randomly selects 10 sub-plots from each of the 4 main plots, for a total of 40 subplots to perform her experiment on. What type of sampling is this? D Stratied Sampling 0 Simple Random Sample 0 |Convenience Sampling