The world's smallest mammal is the bumblebee bat. The mean weight of 15 randomly selected bumblebee bats is 1.659 grams, with a standard deviation of 0.264 grams.
1. Find a 99.9% confidence interval for the mean weight of all bumblebee bats at the following confidence levels (two places after decimal):(______, ______)
2. Find a 99% confidence interval for the mean weight of all bumblebee bats at the following confidence levels (two places after decimal):(______, ______)
3. Find a 95% confidence interval for the mean weight of all bumblebee bats at the following confidence levels (two places after decimal):(______, ______)
4. Find an 80% confidence interval for the mean weight of all bumblebee bats at the following confidence levels (two places after decimal):(______.______)