A cryptanalyst has determined that the three most common tri- (a.) graphs in a ciphertext are LME, WRI, and ZYC, and guesses that these ci- phertext trigraphs correspond to the three most common...

Extracted text: A cryptanalyst has determined that the three most common tri- (a.) graphs in a ciphertext are LME, WRI, and ZYC, and guesses that these ci- phertext trigraphs correspond to the three most common trigraphs in English text, THE, AND, and THA. If the plaintext was encrypted using a Hill tri- graphic cipher described by C = AP (mod 26), what are the entries of the 3 x 3 encrypting matrix A?