Numerade

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Using the GSS84.SAV dataset in SPSS, find 95% and 99% confidence intervals for the mean age and for the proportion female in the sample (four confidence intervals, in total). Use SPSS to get the summary statistics only; calculate the confidence intervals by hand, and show all work. Be sure to include your calculations, interpretations (!), and conclusions.

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What does a range (e.g., 400...417) represent in a switch case? Question 6Select one: a. A set of single values that must match b. A continuous set of numbers within specified bounds c. An optional condition that may or may not match d. A fallback for cases that fail

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Question content area Part 1 A biologist is monitoring the population of a rare species of Snipe. The initial population size was 458 snipes. After only 10 year(s), a new count was taken revealing 625 snipes. Assuming the population of snipes is best modeled with an exponential function, estimate the number of snipes in the count taken after a total of 16 years. enter your response heresnipes

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7. In a study of the association between sleep duration and mortality, Xiao et al (Am J Epidemiol 2014) recruited a large cohort of subjects 51 to 72 years of age, and followed them over time. Their final analysis cohort consisted of 239,896 subjects. Among the many covariates they examined was body mass index (BMI), a measure of body size (measured in kg/m²). Among the 6,054 individuals that reported < 5 hours of sleep per night, the mean BMI was 28.3 with a standard deviation of 5.6, whereas among the 150,966 individuals that reported 7-8 hours of sleep per night, the mean BMI was 26.5 with a standard deviation of 4.4. Calculate a 95% confidence interval for the population mean BMI for each of these two sleep duration groups.

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The nuclear membrane reappears in mitosis during Select one: a. metaphase. b. anaphase. c. telophase. d. interphase. e. prophase.

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A marketing company is conducting an experiment on two different kind of email messages (Email A and Email B) to clients. They want to compare the response rates (proportion of clients who reply to the email). H0: p1 = p2 (The response rate for Email A is similar to Email B) Ha: p1 > p2 (The response rate for Email A is greater than Email B) Part 1: The company decides to use a significance level of 0.05 with a sample size of 3000 for each. Calculate the eta -error assuming the actual response rate for Email A is 0.60 and for Email B is 0.55. Part 2: If the company desired to achieve a power of 0.90 for the test, estimate the necessary sample size for each email type. Assume that the true proportions remain the same

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Book Problem 15 The following limit $\lim_{n \to \infty} \sum_{i=1}^{n} x_i \cos(x_i)\Delta x,\ [0, 2\pi]$ is equal to the definite integral $\int_a^b f(x) \, dx$ where $a = 0$, $b = 2$, and $f(x) = \boxed{\qquad}$

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U A(x, y) = 2x + y U B (x, y) = 2x + 5y eA x = 100, eA y = 100, eB x = 100, eB y = 100 (hint: each consumer will only consume one type of good in equilibrium. Why? Can you guess which good each consumer will consume?)

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Consider a circular fin with diameter D and length 4L attached to a base. Thermocouples are used to measure the temperatures at four locations included in the figure. The measured temperatures are $T_1$, $T_2$, $T_3$ and $T_4$. The surrounding air is at temperature $T_\infty$ and convection coefficient h. You may ignore heat loss through the tip. Based on information given, give your best estimation for the total heat loss from the entire fin. a) $\dot{Q} = hDL(T_1 - T_\infty) + hDL(T_2 - T_\infty) + hDL(T_3 - T_\infty) + hDL(T_4 - T_\infty)$ b) $\dot{Q} = h\pi D^2 (T_1 - T_\infty)/4 + h\pi D^2 (T_2 - T_\infty)/4 + h\pi D^2 (T_3 - T_\infty)/4 + h\pi D^2 (T_4 - T_\infty)/4$ c) $\dot{Q} = h\pi D^2 L(T_1 - T_\infty)/4 + h\pi D^2 L(T_2 - T_\infty)/4 + h\pi D^2 L(T_3 - T_\infty)/4 + h\pi D^2 L(T_4 - T_\infty)/4$ d) $\dot{Q} = hDL(T_1 + T_\infty)/2 + hDL(T_2 + T_\infty)/2 + hDL(T_3 + T_\infty)/2 + hDL(T_4 + T_\infty)/2$ e) $\dot{Q} = h\pi D^2 (T_1 + T_\infty)/8 + h\pi D^2 (T_2 + T_\infty)/8 + h\pi D^2 (T_3 + T_\infty)/8 + h\pi D^2 (T_4 + T_\infty)/8$

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8) In an isolated system, two equal quantities of water, each of mass m, at initial temperatures $T_1$ and $T_2$ are mixed together.\ a) Show that the resulting change in entropy is given by the expression\\ $\Delta S = 2mC_p \ln A$ with $A = (T_1+T_2)/(2\sqrt{T_1T_2})$\ where $C_p$ is the specific heat capacity of water at constant pressure.\ b) Prove that the change in entropy given by this expression is always positive if the two temperatures are not equal.

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lu-s v.