1. You want to estimate the mean number of water hand pumps in Indian villages. You obtain a random sample of 150 villages. In your sample, the mean number of water hand pumps is 14.35. You know that the standard deviation of water hand pumps is 22.10.1.

(a) Calculate a 99% confidence interval for the mean number of water hand pumps in Indian villages.

(b) Based on this 99% confidence interval, would you say that a value for the population mean of 20 water hand pumps is reasonable?

2. In a criminal trial, a defendant is found guilty if the evidence suggests he or she is guilty "beyond a reasonable doubt". In a civil case, a defendant is found guilty if the "preponderance of evidence" suggests he or she is guilty, that is, if it is more likely than not that the defendant is guilty. In which type of trial is the significance level for the evidence larger?