Problem 1 (40 points)

The following plaintext MAJORCONTRIBUTIONWASTHEUSEOFMATH was encrypted by Hill Cipher with 2X2 key matrix and the correspondent ciphertext is KWHGLIDRQVRPFRECPQEGIJCOAEHXKWI. Find a key matrix. EXPLAIN IN DETAIL EACH STEP!

Problem 2 (40 points)

The ciphertext is VFCKOLQOBPTEJENAFJCHBEXS
Part of plaintext is lessplastic
Find Matirx Key and decrypt the message. EXPLAIN IN DETAIL EACH STEP! To decrypt you can use the applet.

Problem 3 (15 points)

The ciphertext is KGYXSH
Part of plaintext is MASTER
Find Matirx Key and decrypt the message, IF POSSIBLE. EXPLAIN IN DETAIL EACH STEP!

Problem 4(5 points)

Give an example of the plaintext/ciphertext pair for which it is impossible to find the key.