Question 4. The average distance between any two stars in our galaxy is on average 5 light years (Earth and our closest neighbour are about 4 light years apart). This distance is deemed to be normally distributed with a standard deviation of 0.7. Part A. [4 Marks] What is the probability that two stars are less than 4 light years apart? Part B. [5 Marks] Scientists are interested in a cluster of 6 stars that are close together. This means there are 6 2 = 15 combinations of two unique stars. What is the probability that the average distance between any two stars in the cluster is between 4.5 and 4.75 light years apart?