Question

hello, I need some help with my problem set. please see the screenshot below.

14. A researcher wants to know what fraction of municipal water sources in Kansas contain hazardous levels of arsenic. The researcher randomly selects 100 municipal water sources and determines that 23 of them have an unsafe level of arsenic. (a) Determine a 99% confidence interval for the proportion. State this interval below within an interpretive sentence tied to the given context. b) The contamination rate of arsenic for all Kansas municipal water sources had previously been reported to be 10%. Is there evidence at the 99% confidence level that the arsenic level is higher than 10%? Explain your reasoning.

Answer 1

29 .23 n. 6.23 2.576 o.2 3 o 23 0-23 0-10 84 6. 1216 0.338 which indiate thor a39 wn fident thot the peutahias 0-1216 0-339 ture wantto test Test statistic is 0.23 0.lo Hene the null hypothesis is rtedeel And we wndludle thot dhoe is ehuugh evidna a ag tasiduna lwel that the asxnic lsiel i highon eve th