Based on the number of voids, a ferrite slab is classified as either high, medium, or low. Historically, 5% of the slabs are classified as high, 85% as medium, and 10% as low. A group of 20 slabs that are independent regarding voids is selected for testing. Let X, Y, and Z denote the number of slabs that are classified as high, medium, and low, respectively. a. What are the name and the values of the parameters of the joint probability distribution of X, Y, and Z