2. (60 points) Consider a CRC code with a generator polynomial of g(x) = x4 + x3 + 1. a. (20 points) Show step by step (using the longhand division) how to find the codeword that corresponds to information bits of 1101. b. (20 points) Show the shift-register circuit that implements this CRC code. C. Suppose the codeword length is 8. Answer the following questions, with proper justifications. i. (10 points) Give an example of undetectable error burst of length 6; ii. (10 points) Give an example of undetectable 6-bit error