Technetium-99 (
a. At noon, the patient is given 10 mCi (millicuries) of
b. At what time will the level of radioactivity reach 3 mCi? Round to the nearest tenth of an hour.
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EBK COLLEGE ALGEBRA & TRIGONOMETRY
- Repeat Example 5 when microphone A receives the sound 4 seconds before microphone B.arrow_forwardSoil samples were collected at two areas surrounding an abandoned mine and analyzed for lead. At each area several samples were taken. The soil was extracted with acid, and the extract was analyzed using flame atomic absorption spectrometry. In Area A, Pb concentrations were 1.2, 1.0, 0.9, 1.4 mg/kg. In Area B, Pb concentrations were 0.7, 1.0, 0.5, 0.6, 0.4 mg/kg. Are these two areas significantly different from each other with Pb concentrations at 90% confidence level?arrow_forwardNumber 2 pls.arrow_forward
- A researcher is testing the effect of a new cold and flu medication on reaction time. A sample of n = 9 students is obtained and each student is given the normal dose of the medicine. Thirty minutes later, each student's reaction time is measured. The scores for the sample averaged M = 211 milliseconds with SS = 1152. Reaction time for students in the regular population averages µ= 200 milliseconds. Set the level of significance at an α = .05, using a two-tailed test.arrow_forwardA dietitian wishes to see if a person’s cholesterol level will change if the diet is supplemented by a certain mineral. Six randomly selected subjects were pretested, and then they took the mineral supplement for a 6-week period. The results are shown in the table. (Cholesterol level is measured in milligrams per deciliter.) Can it be concluded that the cholesterol level has been changed at α = 0.10? Assume the variable is approximately normally distributed. Subject 1 2 3 4 5 6 Before (x1) 210 235 208 190 172 244 After (x2) 190 170 210 188 173 288 Required Steps: Step 1: Label all given information. Step 2:State the null and alternative hypothesis and identify the claim. Step 3:Verify that the conditions are met to perform the test. Step 4:Sketch the normal distribution and find the critical regions. Step 5:Compute the test statistic. Step 6:Make a decision Step 7:Summarize the results.arrow_forwardThe difference in the observed neurological disease rate, xbar, for a sample of veterans who served in Iraq is not “statistically significantly different” (alpha = .05), from the overall population disease rate for all U.S. veterans, mu0. This means: a. xbar = mu0b. The disease rates xbar and mu0 are not equal, but the size of the difference is not practically important, not big enough to matter. c. H0: mu for Iraq vets = mu0 was not rejected d. None of the abovearrow_forward
- A manufacturer wants to increase the shelf life of a line of cake mixes. Past records indicate that the average shelf life of the mix is 216 days. After a revised mix has been developed, a sample of nine boxes of cake mix gave these shelf lives (in days): 215, 217, 218, 219, 216, 217, 217, 218, and 218. Using α = 0.025, has the shelf life of the cake mix increased?arrow_forwardThis question is about Experimental design.arrow_forwardLichen has a high absorbance capacity for radiation fallout from nuclear accidents. Since lichen is a major source for Alaskan caribou, and caribou is major food source tor the Alaskan villagers, it is important to monitor the level of radioactivity in lichen. Researcher at the University of Alaska, Fairbanks, collected 9 lichen specimens and measured the amount in micro-curies per milliliter) of the radioactive element cesium-137 for each. Using the Minitab software, it was found that the mean and standard deviation for the 9 observations were X = 0.009027 аnd s = 0.004854 A) Give a point estimate for the mean amount of cesium in lichen specimens collected in Alaska. B) Give the t- value used in a small sample 95% confidence interval for the true mean amount of cesium in Alaskan lichen specimens. C) Form a 95% confidence interval for the true mean amount of cesium in Alaskan lichen specimens. D) Give a practical interpretation for the interval you obtained in part C. E) What…arrow_forward
- A pilot study was performed to investigate the effect of temperature, x (in degree Fahrenheit) on the electrical power consumed, y (in Watt) by an automotive factory. Other factors were kept constant and the data were collected from the study. The summary of the data are given as follows: n = 8, 2x = 401, 2301, x? = 22495 2y? = 666509, Σ > xy = 118652. %3D Compute the equation of the least squares regression line of y on x. Interpret the equation obtained in part (i). Predict the power consumption for a temperature of 65°F. (i) (ii) (iii) (iv) Compute the coefficient of determination and explain.arrow_forwardPlease use alpha= 0.05. thak uarrow_forwardOtitis media is a disease that occurs frequently in the firstfew years of life and is one of the most common reasonsfor physician visits after the routine checkup. A study wasconducted to assess the frequency of otitis media in thegeneral population in the first year of life. Table 4.15 givesthe number of infants of 2500 infants who were first seen atbirth who remained disease-free by the end of the ith monthof life, i = 0, 1, . . . , 12. (Assume no infants have been lostto follow-up.) Disease-free infants ati the end of month i0 25001 24252 23753 23004 21805 20006 18757 17008 15009 130010 125011 122512 1200 Suppose an “otitis-prone family” is defined asone in which at least three siblings of five develop otitis media in the first 6 months of life. What proportionof five-sibling families is otitis prone if we assume thedisease occurs independently for different siblings in afamily?arrow_forward
- Trigonometry (MindTap Course List)TrigonometryISBN:9781337278461Author:Ron LarsonPublisher:Cengage Learning