A large number of consecutive IP addresses are available from 198.16.0.0. Suppose that four companies A, B, C and D respectively require 4000,2000,4000 and 8000 addresses (requests arrive in that order). Please answer the following questions: 1. the first IP address assigned for company A, B, C, and D, 2. the last IP address assigned for company A, B, C, and D, 3. the allocated block for company A, B, C, and D, using the notation w.x.y.z/s. This problem is about CIDR: Classless Inter-Domain Routing