Use the PART III provided in the simulation page to solve the following problems. The tool includes a shift cipher calculator and a workspace for your analysis.

1. Encrypt the following plaintext using key k= 7.

Given:

• Plaintext: Lord Rama was a good king.
• Key: k = 7

2.Given a plaintext and its corresponding ciphertext, determine the key used for encryption.

Given:

• Plaintext: abcdefghijklmnopqrstuvwxyz
• Ciphertext: tuvwxyzabcdefghijklmnopqrs

Hint: Compare the first few letters: a→t, b→u, c→v...

3. How many different keys are possible with an n-letter alphabet?

4. For English alphabet (n=26): How many distinct keys exist?

5. Decrypt the following ciphertext using brute force attack.

Given: Ciphertext: HAAHJR HA KHDU