Linear Regression and Correlation Problem One of the more challenging problems confronting the water pollution control field is presented by the tanning industry. Tannery wastes are chemically complex. They are characterized by high values of biochemical oxygen demand, volatile solids, and other pollution measures. A study conducted by Virginia Polytechnic Institute and State University measured the percent reduction in total solids (x) and percent reduction in chemical oxygen demand (y) of 33 samples of chemically treated waste. Table 11.1: Measures of Reduction in Solids and Oxygen Demand Solids Reduction, Oxygen Demand Reduction, y (%) z (%) 3 Solids Reduction, z (%) 36 Oxygen Demand Reduction, y (%) 34 7 11 37 36 11 21 38 38 15 16 39 37 18 16 39 36 27 28 39 45 29 27 40 39 30 25 41 41 30 35 42 40 31 30 42 44 31 40 43 37 32 32 44 44 33 34 45 46 33 32 46 46 34 34 47 49 36 37 50 51 36 38 a. Using a = 0.01, test H: ß1 = 0 vs. Hl: B1 6= 0 b. Imagine that the next solid reduction level is at 54%. what would be your best estimate of the oxygen demand reduction?