28. Farmers The logistic model 14,656,248 W(t) 1+ 0.059e0.057 represents the number of farm workers in the United States I years after 1910. (a) Evaluate and interpret W(0). (b) Use a graphing utility to graph W = W(1). (c) How many farm workers were there in the United States in 2010? (d) When did the number of farm workers in the United States reach 10,000? (e) According to this model, what happens to the number of farm workers in the United States as i approaches ? Based on this result, do you think that it is reasonable to use this model to predict the number of farm workers in the United States in 2060? Why? Source: U.S. Department of Agriculture

Write the equation in the slope intercept form for the linear function

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1. Graph f(x) = log2 × carefully. your work.) %3D 10 -10 -5 10 -5- -10

Consider the plot of the total number E of Ebola cases in West Africa reported to the Centers for Disease Control and Prevention from April 1, 2014, through December 1, 2015. D +|+|||||||||||||||| ► Ebola Cases in West Africa E = A logistic fit for these data is given by 27,841.42 1 + 134.65-0.646 where t is the time in months since April 1, 2014. Below, we have added the graph of this model. +-+|||||||||||||||||| ► Logistic Graph Added (a) Does the first plot, "Ebola Cases in West Africa," show a continuing epidemic or a health crisis that is under control by December 2015? Because the data points appear to be [leveling off ✔✔✔, they show a health crisis that is under control (b) According to the model, what was the total number of cases when the disease was spreading at the fastest rate? Round your answer to the nearest whole number. 27021.61 x cases (c) Use the crossing-graphs method to determine when the disease was growing at the fastest rate. Round your answer, in months after…

1. Chemical Acidity In chemistry, the acidity of a water-based solution is measured by the concentration of hydrogen ions in the solution (in moles per liter). The hydrogen-ion concentration is written [H*]. Because such concentrations usually involve negative powers of ten, negative orders of magnitude are used to compare acidity levels. The measure of acidity used is pH, the opposite of the common log of the hydrogen-ion concentration: pH = -log[H] More acidic solutions have higher hydrogen-ion concentrations. A certain brand of lemon juice has a pH of 2.1, and a certain brand of cleaning ammonia has a pH of 11.6. a) Find the hydrogen-ion concentrations for the lemon juice and the ammonia. b) How many times greater Is the hydrogen-ion concentration of the lemon juice than the ammonia?

8. Which exponential equation matches the graph shown? (1,6) (0,2) a. c. b. y- 2(3)* d. y-2(3)"

The logistic model P(t) = 96.0235 1+0.0455-0.1864t represents the percentage of households that do not own a personal computer t years since 1983. Complete parts (a)-(d). (a) Evaluate and interpret P(0). Evaluate P(0). P(0) = 91.8 % (Round to one decimal place as needed.) Which sentence below best describes P(0)? O A. P(0) is the year all households had a personal computer. O B. O C. O D. P(0) is the year no households had a personal computer. P(0) is the percentage of households with a personal computer in 1983. P(0) is the percentage of households without a personal computer in 1983. -C