Part A: 4. Design a 2 x 2 Encoding Matrix, C. The Encoding Matrix must be invertible. Show your working for computing C.". Message Encryption 5. Convert your result from Part 3 into a m x 2 matrix, M, where m depends on the length of the message. For example, the following row of numbers 13 5 18 2 24 8 is rewritten as 13 5 18 2 24 B 6. Encrypt your message S by multiplying M by C. This cyphertext is sent to the receiver. S = MC Message Decryption 7. Since S = MC and C is invertible, obtain the original the original result in part 3 in m x 2 matrix form, by performing M = SC-1. 8. Convert your results in part 7 to original plain text using the Alpha to Numeric Substitution Table.Part B: As an upgrade to your system in Part A, you are to make the following improvements to it: (a) Replace the 2 x 2 Encoding Matrix C with a 3 x 3 Matrix. Find the inverse of the Encoding Matrix, C-1. (b) Instead of having numeric equivalent of your message M in the form of a m x 2 matrix, rearrange it in the form of 3 x 1 matrices. For example, the sample message M matrix in Step (5) 13 5 18 2 24 8 can be rewritten as 2 matrices of size 3 x 1: 13 2 M1 = 5, M2= 24 18 8 The ciphertext can then be obtained as follows : S1 = CM1, $2=CMz etc Required: Based on the above new requirements, rework Stops 4 to 8 in Part A. Showing all workings. To keep the exercise manageable, you only need to perform encryption and decryption for only the first 3 characters of your plain text message