Answer both questions with explanation

b) Assuming that the cost of collecting data is the same everywhere, use the variances from the study to plan next year?s study, with a goal of getting an optimal allocation with a margin of error of 1 ppt. 2. I want to know the average contamination level in a plot of ground. Just by looking at the area, I see that part has discolored soil and damaged plants. I'll put this area into one stratum and the rest of the area into another stratum. I collect it = 3 measurements in each stratum: Stratum One (appears contaminated): Area = 5 hectares, Measurements = 50 ppt, 100 ppt, 75 ppt. Stratum Two (appears uncontaminated): Area = 45 hectares, Measurements = 1 ppt, 3 ppt, 2 ppt. a) Find a 95 percent condence interval for the true mean contamination level