True/False:

1. Symmetric encryption remains by far the most widely used of the two types of encryption. 2. Symmetric encryption is a form of cryptosystem in which encryption and decryption are performed using different keys. It is also known as non-conventional encryption. 3. With the use of symmetric encryption, the principal security problem is maintaining the secrecy of the key. 4. The process of converting from plaintext to ciphertext is known as deciphering or decryption. 5. The algorithm will produce a different output depending on the specific secret key being used at the time. The exact substitutions and transformations performed by the algorithm depend on the key. 6. When using symmetric encryption it is very important to keep the algorithm secret. 7. On average, half of all possible keys must be tried to achieve success with a brute-force attack. 8. Ciphertext generated using a computationally secure encryption scheme is impossible for an opponent to decrypt simply because the required information is not there. 9. Monoalphabetic ciphers are easy to break because they reflect the frequency data of the original alphabet.