Answer Happy

3. The article “The Incorporation of Uranium and Silver by Hydrothermally Synthesized Galena” (Econ. Geology, 1964: 1003-1024) reports on the determination of silver content of galena crystals grown in a closed hydrothermal system over a range of temperature. With x = crystallization temperature in °C and y = Ag2S in mol%, the summary data follows: Xx, = 6130 < y; = 4.73 {x} = 3,022,050 < x;y; = 2418.74 Ey? = B2 = 0.00143, B. =-0.311, ã = 471.54, n=13, and s = 0.131. a) Estimate the true average silver content when the temperature is 500°C using a 95% confidence interval. b) How would the width of a 95% confidence interval for true average silver content when temperature is 400°C compare to the width of the interval in part (a)? Answer this question by considering your answer to Question #2 above, not by actually computing the interval. Explain your reasoning. c) Calculate a 95% confidence interval for the true average change in silver content associated with a 1°C increase in temperature. Hint: You can find Sex with the information provided above using a formula on the bottom of pg. 117. d) Predict the silver content for a single observation to be made when temperature is 500°C using a 95% prediction interval. Comment on how your prediction calculated here compares to the estimate you calculated in (a). Is this what you would expect? Explain.