Name:A 2015 Virginia Tech study reported that out of a sample of 252 homes in Flint, Michigan, 42 of them had over 15 ppb oflead in their drinking water. At the 1% significance level, is it indicated that the city of Flint exceeded the EPA standard?Part A: Write the null hypothesis in symbols and in a complete sentence.Part B: Write the alternative hypothesis in symbols and in a complete sentence.Part C: Verify that the conditions for the one-sample z-test for proportions have been met.Part D: Calculate the test statistic and P-value.Part E: Will the null hypothesis be rejected? Explain.Part F: At the 1% significance level, do the data indicate that the city of Flint exceeded the EPA standard? Explain.Why do you think a 1% significance level is used here? Why not 10%? Or 5%?Suppose our sample resulted in a P-value of 0.023. Would it be okay to make a conclusion at the 5% significance levelinstead?The NIDA was interested in the effects of the 2020 pandemic on drug abuse in teens. In particular, they were interestedin understanding the change between pre-pandemic vaping usage and vaping usage three months into the pandemic.Before the pandemic, 24% of 12th graders reported that they had vaped nicotine in the past 30 days.The study included 582 12th graders who anonymously completed the MTF survey. Three months into the pandemic,17% of 12th graders reported that they had vaped nicotine in the past 30 days.Part A: What is the null hypothesis for the study?Part B: What is the alternative hypothesis?Part C: Calculate the P-value for the test.Part D: At the 5% significance level, do you reject the null hypothesis?herein exceediPart E: What is the conclusion?Part F: Was your conclusion in Part E statistically significant? Was it practically significant?Part G: Can you be absolutely certain in your conclusion? In other words, can you be absolutely 100% certain of yourconclusion?

Note: In case of multiple questions, as per the guidelines answer to one question will be provided. Here, question 1 is incomplete as it does not have population proportion. The answer has been provided for question 2. Let p denotes the population proportion of the number of 12 graders who vaped nicotine in the past 30 days.The given problem tests the prevalence of nicotine among 12 graders pre pandemic and three months into the pandemic. Under the hypothesis: A. Null hypothesis, H0: There is no change in vaping usage after three months into pandemic, i.e., p=0.24 B. Alternate hypothesis, H1: There is a significant change in vaping usage after three months into pandemic, i.e., p≠0.24 C. Sample size, n=582 Sample proportion, p^=0.17 Test statistic for one sample z test for proportion is: z=p^-pp1-pn=0.17-0.240.24×0.76582=-3.9541 The P-Value can be calculated using the excel function: =2*NORM.S.DIST(-3.9541,TRUE) P-Value ≅ 0.0001D. At 5% level of significance, as P-Value < 0.05, we have sufficient evidence to reject the null hypothesis. E. There is a significant change in vaping usage after three months into pandemic. F. Yes, the results are statistically significant at 5% level of significance. The practical significance of drug usage lies in the absolute decrease in the usage of drugs. The pandemic brought lockdowns, but then also the decrease in drug usage according to the sample selected was not very large when compared to the population. So, these results might not be significant practically. G. We cannot be 100% sure of the conclusion. This is because the conclusion was based on a random sample.