Use the following information: A researcher is interested in examining the difference in the average egg incubation temperature of two lizards in North Carolina, the native green anoles versus the invasive brown anoles. To investigate this, she takes two random samples from both of the lizard populations and calculates the average egg incubation temperature, standard deviation, and sample size for each of the two samples.
The average incubation temperature for the 25 sampled brown anoles is 83.2 degrees F, with a sample standard deviation of 20.2 degrees F. The average incubation temperature the 28 samples green anoles is 80.1 degrees F, with a sample standard deviation of 17.4 degrees F. She has also determined that the two samples do not exhibit strong skewness and appear approximately normal.
A. Determine the appropriate t, critical value for a 99% confidence interval for the difference between the true mean incubation temperatures for the two different anole species, mu1 - mu2.
B. Determine the standard error for the 99% confidence interval for the difference between the true mean incubation temperatures for the two different anole species, mu1 - mu2.