The world's smallest mammal is the bumblebee bat. Such bats are roughly the same size of a large bumblebee. Listed below are the weights (in grams) from a sample of these bats. Assuming that all such bats have a standard deviation of .3 grams, use a significance level of .05 to test the claim that these bats are from the same population with a known mean of 1.8 grams. Do the bats appear to be from the same population ? You may assume the sample data comes from a population that follows a normal distribution.
2.13 1.31 1.91 1.92 1.77 1.64 2.29 1.99 2.33 2.49 2.22