Please do it on maple software if possible. Thank you.

Peter receives from Alice a number text 21 21 24 04 12 00 23 25 04 07 05 09 11 10 19 13 encoded by a Hill cryptosystem using 26 character-to-number conversion table 1 2 3 4 5 6 7 8 9 "A" "B" "C" "D" "E" "F" "G" "H" "I" 10 11 12 13 14 15 16 17 18 "J" "K" "L" "M" "N" "O" "P" "Q" "R" 19 20 21 22 23 24 25 26 "S" "T" "U" "V" "W" "X" "Y" "Z" with the character "Z" used also for space "_" He knows that for encryption Alice was using one of the following matrices. 1 > A = ((3. 23, 11, 0)|(6, 5, 10, 13) (0, 16, 25, 25)|(9.8. 18. 15)); B:= ((10. 1, 15, 11)|(1.2.11, 7)|(13, 5.2. 17)|(9, 2. 13. 7)): A:= 3 6 0 9 23 5 168 11 10 25 18 0 13 25 15 10 1 13 9 1 2 5 2 15 11 2 13 11 7 17 7 B:= but he doesn't remember which one. He checks which one of these two matrices could have been used and finds unambiguously that only one is appropriate for encryption. Give an argument that allowed Peter to choose between matrices A and B. Use the matrix you have chosen to perform the decryption of the number text received by Peter and find the original text sent by Alice Peter receives from Alice a number text 21 21 24 04 12 00 23 25 04 07 05 09 11 10 19 13 encoded by a Hill cryptosystem using 26 character-to-number conversion table 1 2 3 4 5 6 7 8 9 "A" "B" "C" "D" "E" "F" "G" "H" "I" 10 11 12 13 14 15 16 17 18 "J" "K" "L" "M" "N" "O" "P" "Q" "R" 19 20 21 22 23 24 25 26 "S" "T" "U" "V" "W" "X" "Y" "Z" with the character "Z" used also for space "_" He knows that for encryption Alice was using one of the following matrices. 1 > A = ((3. 23, 11, 0)|(6, 5, 10, 13) (0, 16, 25, 25)|(9.8. 18. 15)); B:= ((10. 1, 15, 11)|(1.2.11, 7)|(13, 5.2. 17)|(9, 2. 13. 7)): A:= 3 6 0 9 23 5 168 11 10 25 18 0 13 25 15 10 1 13 9 1 2 5 2 15 11 2 13 11 7 17 7 B:= but he doesn't remember which one. He checks which one of these two matrices could have been used and finds unambiguously that only one is appropriate for encryption. Give an argument that allowed Peter to choose between matrices A and B. Use the matrix you have chosen to perform the decryption of the number text received by Peter and find the original text sent by Alice