Math Homework Help

Question #1: Convert the plaintext “PRIME” into ciphertext by using multiplication by 5 in the mod 26 multiplicative cipher system. Provide written evidence of your work/computations.

Question #2: When using a multiplicative cipher system in mod 26, how many different values can be used for the “multiply by” number? Explain/Justify how you arrived at your answer.

Question #3: How does using a prime mod value make a multiplicative cipher system more secure than a non-prime mod? Explain/Justify your answer.

Question #4: The ciphertext “dqw9” was created using a multiplicative key of 4 in mod 37. Convert the ciphertext “dqw9” back into plaintext.