1) [5 pts] Compute P(Z

2) [5 pts] An electrical firm manufacturers light bulbs that have a life, before burn-out, that is normally distributed with mean equal to 800 hours and a standard deviation of 40 hours. Find the probability that a bulb burns between 778 and 834 hours.

3) Many people consider themselves "green", meaning they are supportive (in theory) when it comes to environmental issues. But, how do they act in practice? For instance, Americans' per capita use of energy is roughly double that of Western Europeans. If you live in North America, would you be willing to pay the same price for gas that Europeans do (often about $6 or more per gallon), if the government proposed a significant price hike as an incentive for conservation and for driving more fuel-efficient cars to reduce air pollution and its impact on global warning?

In 2000, the General Social Survey asked subjects if they would be willing to pay much higher prices in order to protect the environment. Of n=1154 respondents, 518 indicated a willingness to do so. That is, the sample proportion p= 518/1154= 0.4489.

A. [10pts] Find a 95% confidence interval for the population proportion of adult Americans willing to do so at the time of that survey.

B. [10pts] Interpret the interval.

C. [10pts] Suppose the survey result of p=0.4489 had resulted from a sample of size n=288. Calculate the 95% confidence interval for this sample size and assess the effects of sample size on the interval.

Web Login X STA-1053-005-Spring-202'I-B... Web Login X STA-1053-005-Spring-202'I-B... E) Quizzes and Exams 1) [5 pts] Compute P(Z