A standard method (based on thousands of measurements) for CO2 analysis has a standard deviation of 1 ppm. A modified method has a standard deviation of 0.5 ppm, for 20 degrees of freedom? With 95% confidence, is this alternative method more precise?

Currently patrons at the library speak at an average of 66 decibels. Will this average decline after the installation of a new computer plug in station? After the plug in station was built, the librarian randomly recorded 66 people speaking at the library. Their average decibel level was 63.2 and their standard deviation was 18. What can be concluded at the the a = 0.10 level of significance? a. For this study, we should use Select an answer b. The null and alternative hypotheses would be: Ho: ?v Select an answer v Hị: Select an answer c. The test statistic ? v (please show your answer to 3 decimal places.) d. The p-value = (Please show your answer to 4 decimal places.) e. The p-value is ? va f. Based on this, we should Select an answer g. Thus, the final conclusion is that ... | the null hypothesis. OThe data suggest that the population mean decibal level has not significantly decreased from 66 at a = 0.10, so there is statistically insignificant evidence to conclude that the…

Although, it is commonly believed that the mean for the human body temperature is 98.6 F, others doubt it. A random sample of 100 persons showed the mean body temperature to be 98.4 F with standard deviation of .76 F. At a .05 level of significance, find if the data indicates that the mean for the human body temperature is not equal to 98.6.  Find tcritical  or tcr

Currently patrons at the library speak at an average of 64 decibels. Will this average change after the installation of a new computer plug in station? After the plug in station was built, the librarian randomly recorded 69 people speaking at the library. Their average decibel level was 61.7 and their standard deviation was 6. What can be concluded at the α = 0.05 level of significance?      H0:H0:  ? μ p  Select an answer > ≠ < =         H1:H1:  ? p μ  Select an answer = > < ≠     The test statistic ? t z  =  (please show your answer to 3 decimal places.) The p-value =  (Please show your answer to 4 decimal places.)