One dimension of bird beaks is "depth"--the height of the beak where it arises from the bird's

head. During a research study on one island in the Galapagos archipelago, the beak depth of all

Medium Ground Finches on the island was found to be normally distributed with mean y = 9.6

millimeters and standard deviation o=1.1 millimeter. What is the probability that the mean

depth in 15 randomly selected Medium Ground Finches is at least 10 millimeters?