Answer:
Step-by-step explanation:
a) Estimate for population mean = Sum/n =![\frac{59.1}{12} =4.925](https://tex.z-dn.net/?f=%5Cfrac%7B59.1%7D%7B12%7D%20%3D4.925)
b) Variance = 0.099208
Std dev = 0.314974
Std error = 0.0950
For 95% margin of error = 1.96*Std error
=0.1861
Confidence interval = ![(4.925-0.1861, 4.925+0.1861)\\=(4.7389, 5.1111)](https://tex.z-dn.net/?f=%284.925-0.1861%2C%204.925%2B0.1861%29%5C%5C%3D%284.7389%2C%205.1111%29)
Interpretation of confidence interval:
A) if repeated samoles are taken, 95% of them will have a sample pH of rain water between [ ] & [ ].
For 99% CI, z value = 2.59
Conf interval = (4.6790, 5.1710)
C)if repeated samoles are taken, 99% of them will have a sample pH of rain water between [ ] & [ ].
As the level of confidence increases l, the width of the interval[ increases] this makes sense since the [ margin of error] [increases]