[6] in cryptography we often use matrix operations but modulo some m for the calculations (for example, in hill substitution ciphers.) do the following mod 26 calculations: 2. compute the following matrix product modulo 26 a. [17 22 41 [21 1 18] 1125 22 20 13 17 24 19 2 9 4 6 b. a "key matrix" is use to encode a message where blocks of letters are replaced by blocks of numbers (for example, bad might become 204.) to decrypt the message, it is necessary to invert the key matrix (mod 26). if the key matrix is given as, [10 18 a = |17 1 1 7 21 4 then compute a-1 mod 26. (hint: row reduce the augmented matrix using modulo 26 calculations. recall that the modulus of a number n is the reminder after dividing by the modulus m. for example, 55 is equal to (we say "congruent to") 3 modulus (or "mod 26") since 55 = 2(26) 3.) you may use software to assist doing this.