In: Advanced Math
a. Solve 7x + 5 ≡ 3 (mod 19).
b. State and prove the Chinese Remainder Theorem
c. State and prove Euler’s Theorem.
d. What are the last three digits of 9^1203?
e. Identify all of the primitive roots of 19.
f. Explain what a Feistel system is and explain how to decrypt something encoded with a Feistel system. Prove your result.