In "Egg Size, Fertility, Hatchability, and Chick Survivability in Captive California Condors," published in the journal Zoo Biology in 2005, researchers considered the lengths in millimeters of 100 eggs that were in the second laying of the season. They reported results Mean + SE to be 105.70 + 0.48.10
a. Explain why the multiplier in a confidence interval for population mean may be identified as z instead of t.
b. Keeping in mind that an approximate 95% confidence interval is sample mean plus or minus 2 standard errors, report an approximate 95% confidence interval for the mean length of all captive condor eggs in the second laying of the season.
c. Keeping in mind that standard error is calculated as sample standard deviation divided by square root of sample size ( ), report the sample standard deviation s for those 100 eggs.