Please use the accompanying Excel data set or accompanying Text file data set when completing the following exercise. An article in Process Engineering (No. 71, 1992, pp. 46-47) presents a two-factor factorial experiment used to investigate the effect of pH and catalyst concentration on product viscosity(cSt). The data are as follows: Catalyst Concentration 2.5 2.7 5.6 192 199 189 198 178 186 179 188 pH 5.9 185 196 204 204 193 185 192 197 (a) Test for main effects and the interaction using a = 0.05. Round your answers to two decimal places (e.g. 98.76). pH: Fo = Catalyst Concentration: Fo= i pH Catalyst Concentration: Fo D

Please use the accompanying Excel data set or accompanying Text file data set when completing the following exercise. An article in Journal of Food Science (2001, Vol. 66, No. 3, pp. 472-477) studied potato spoilage based on different conditions of acidified oxine (AO), which is a mixture of chlorite and chlorine dioxide. The data are shown below: AO Solution (ppm) % Spoilage 50 100 50 60 100 60 30 30 200 60 50 29 400 25 30 15 (a) Do the AO solutions differ in the spoilage percentage? Use a = 0.05. There is for significant differences in the spoilage percentage when using different AO solutions. (b) Find the P-value of the test. Estimate the variability due to random error. P-value = i (Round your answer to three decimal places.) MSE = i . (Round your answer to the nearest integer.) (c) Plot average spoilage against AO solution and interpret the results. Which AO solution would you recommend for use in practice? AO solution will be used. (d) Analyze the residual plots to determine…

Samples of both surface soil and subsoil were taken from eight randomly selected agricultural locations in a particular county. The soil samples were analyzed to determine both surface pH and subsoil pH, with the results shown in the accompanying table. 2. 3. 6. Location Surface pH 6.55 5.98 5.59 6.17 5.92 6.18 6.43 5.68 Subsoil pH 6.78 6.14 5.80 5.91 6.10 6.01 6.18 5.88 a. Compute a 90% confidence interval for the mean differend between surface and subsoil pH for agricultural land in this county. b. What assumptions are necessary for the interval in Part (a) to be valid?

Please use the accompanying Excel data set or accompanying Text file data set when completing the following exercise. An article in Urban Ecosystems, "Urbanization and Warming of Phoenix (Arizona, USA): Impacts, Feedbacks and Mitigation" (2002, Vol. 6, pp. 183–203), mentions that Phoenix is ideal to study the effects of an urban heat island because it has grown from a population of 300,000 to approximately 3 million over the last 50 years and this is a period with a continuous, detailed climate record. The 50-year averages of the mean annual temperatures at eight sites in Phoenix are shown below. Check the assumption of normality in the population with a probability plot. Construct a 95% confidence interval for the standard deviation over the sites of the mean annual temperatures. Site Sky Harbor Airport 23.3 Average Mean Temperature (°C) Phoenix Greenway 21.7 Phoenix Encanto Waddell 21.6 21.7