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Suppose that spaces, periods, and question marks are added to the plaintext to increase the key domain of simple ciphers. What is the key domain if an additive cipher is used? (Note: alphabet domain size is 26) Question 1 options: The size of the key domain is 29 The size of the key domain is 28 The size of the key domain is 812 The size of the key domain is 27 Question 2 (1 point) Suppose that spaces, periods, and question marks are added to the plaintext to increase the key domain of simple ciphers. What is the key domain if a multiplicative cipher is used? (Note: alphabet domain size is 26) Question 2 options: The size of the key domain is 29 The size of the key domain is 28 The size of the key domain is 812 The size of the key domain is 27 Question 3 (1 point) Saved In Vigenere cipher, what is the maximum number of characters that will be changed in the ciphertext if only a single character is changed in the plaintext? Question 3 options: Only one character in the ciphertext will be changed All characters in the ciphertext which comes after that character A maximum of two characters Hard to tell Question 4 (1 point) In Playfair cipher, what is the maximum number of characters that will be changed in the ciphertext if only a single character is changed in the plaintext? Question 4 options: Multiple characters Cannot know in advance If one character in the plaintext is changed, it normally changes one or two characters in the ciphertext All the following characters int he cipher Question 5 (1 point) The Playfair is a block cipher; encryption is done two characters at a time. Question 5 options: True False Question 6 (1 point) The autokey cipher is a stream cipher; encryption is done one character at a time. Question 6 options: True False Question 7 (1 point) The one-time pad cipher is a stream cipher; encryption is done one character at a time. Question 7 options: True False Question 8 (1 point) The rotor cipher is a stream cipher; encryption is done one character at a time. Question 8 options: True False Question 9 (1 point) The Enigma machine is a is a stream cipher; encryption is done one character at a time. Question 9 options: True False Question 10 (1 point) The encryption key in a transposition cipher is (3, 2, 6, 1, 5, 4). Find the decryption key. Question 10 options: 1 2 3 4 5 6 4 2 1 6 5 3 4 2 1 6 3 5 2 4 1 6 3 5 Question 11 (1 point) Find the matrix representation of the decryption key for the matrix representation of the transposition-cipher encryption key with the key (3, 2, 6, 1, 5, 4). Question 11 options: 4 2 1 6 5 3 3 2 6 1 5 4 321456 546213 Question 12 (1 point) A symmetric-key encipherment uses a single key for both encryption and decryption. Question 12 options: True False Question 13 (1 point) In Symmetric-key encipherment, the encryption and decryption algorithms are inverse of each. Question 13 options: True False Question 14 (1 point) In monoalphabetic substitution, the relationship between a character in the plaintext and the characters in the ciphertext is one-to-many. Question 14 options: True False Question 15 (1 point) In polyalphabetic substitution, the relationship between a character in the plaintext and the characters in the ciphertext is one-to-many. Question 15 options: True False Question 16 (1 point) Symmetric-key ciphers are either: stream ciphers or block ciphers.In a stream cipher, encryption and decryption are done 8 symbols at a time. Question 16 options: True False Question 17 (1 point) Symmetric-key ciphers are either: stream ciphers or block ciphers.In a block cipher, symbols are encrypted together. Question 17 options: True False Question 18 (1 point) Which of the following are cryptanalysis attacks? Question 18 options: Brute-force attack Statistical attack Pattern attack All of the above Question 19 (1 point) Which of the following are cryptanalysis attacks? Question 19 options: Reply attack ARP Flooding attack Pattern attack None of the above Question 20 (1 point) The rail fence cipher and double transposition cipher are examples of transposition ciphers. Question 20 options: True False Question 21 (1 point) The rail fence cipher is example of polyalphabetic ciphers. Question 21 options: True False Question 22 (1 point) Hill cipher, rotor cipher, one-time pad, and Enigma machine are some examples of polyalphabetic ciphers. Question 22 options: True False Question 23 (1 point) The autokey cipher, Playfair cipher, Vigenere cipher are some examples of transposition ciphers. Question 23 options: True False Question 24 (1 point) A small private club has only 100 members.How many secret keys are needed if all members of the club needed to send a secret message to each other? Question 24 options: 4950 2475 9900 100 Question 25 (1 point) A small private club has only 100 members. How many secret keys are needed if everyone trusts the president of the club? If a member wants to send a message to another member, he or she first sends the message to the president of the club; the president then sends it to the other member. Question 25 options: 101 100 200 1 Question 26 (1 point) Alice Often needs to encipher plain-text made of both letter (a to z ) and digit (0 to 9). If she uses an additive cipher, what is the key domain? What is the modulus? Question 26 options: The size of the key domain is 26 + 10 = 36. The modulus is also 36. Alice needs to use the set Z36 The size of the key domain is 25 + 10 = 35. The modulus is also 36. Alice needs to use the set Z36 The size of the key domain is 36 + 10 = 46. The modulus is also 36. Alice needs to use the set Z36 The size of the key domain is 26 X 10 = 36. The modulus is also 36. Alice needs to use the set Z260 Question 27 (1 point) Alice Often needs to encipher plain-text made of both letter (a to z ) and digit (0 to 9). If she uses multiplication cipher, what is the key domain? What is the modulus? Question 27 options: The size of the key domain is 24; the domain is (1, 5, 7, 11, 13, 17, 19, 23, 25, and 29). The modulus is 72. Alice needs to use the set Z72∗ The size of the key domain is 12; the domain is (1, 5, 7, 11, 13, 17, 19, 23, 25, and 29). The modulus is 36. Alice needs to use the set Z36∗ The size of the key domain is 22; the domain is (1, 5, 7, 11, 13, 17, 19, 23, 25, and 29). The modulus is 36. Alice needs to use the set Z36∗ Not possible to figure it out Question 28 (1 point) Alice Often needs to encipher plain-text made of both letter (a to z ) and digit (0 to 9). If she uses Affine cipher, what is the key domain? What is the modulus? Question 28 options: he key domain is 50 × 12 = 600. The modulus is still 36. However, Alice needs to use Z36 for addition and Z36* for multiplication The key domain is 26 × 2 = 42. The modulus is still 36. However, Alice needs to use Z36 for addition and Z26* for multiplication The key domain is 36 × 12 = 432. The modulus is still 36. However, Alice needs to use Z36 for addition and Z36* for multiplication The key domain is 36 × 12 = 432. The modulus is 46. However, Alice needs to use Z36 for addition and Z36* for multiplication Question 29 (1 point) Encrypt the message "this" using Affine cipher, key = (15, 20). Ignore space between word. Decrypt the cipher text to get original message. Question 29 options: NBCM ZBQK YKEC TVKE Submit Quiz2 of 29 questions Suppose that spaces, periods and question marks are added to the plaintext to increase the key domain of simple ciphers. What is the key domain if an additive cipher is used? (note: alphabet domain size is 26) Question 1 options: The size of the key domain is 29 The size of the key domain is 28 The size of the key domain is 812 The size of the key domain is 27 Question 2 (1 point) Suppose that spaces, periods and question marks are added to the plaintext to increase the key domain of simple ciphers. What is the key domain if a multiplicative cipher is used? (note: alphabet domain size is 26) Question 2 options: The size of the key domain is 29 The size of the key domain is 28 The size of the key domain is 812 The size of the key domain is 27 Question 3 (1 point) Saved In Vigenere cipher, what is the maximum number of characters that will be changed in the ciphertext if only a single character is changed in the plaintext? Question 3 options: Only one character in the ciphertext will be changed All characters in the ciphertext which comes after that character A maximum of two charcters Hard to tell Question 4 (1 point) In Playfair cipher, what is the maximum number of characters that will be changed in the ciphertext if only a single character is changed in the plaintext? Question 4 options: Multiple characters Cannot know in advance If one character in the plaintext is changed, it normally changes one or two characters in the ciphertext All the following characters int he cipher Question 5 (1 point) The Playfair is a block cipher; encryption is done two characters at a time. Question 5 options: True False Question 6 (1 point) The autokey cipher is a stream cipher; encryption is done one character at a time. Question 6 options: True False Question 7 (1 point) The one-time pad cipher is a stream cipher; encryption is done one character at a time. Question 7 options: True False Question 8 (1 point) The rotor cipher is a stream cipher; encryption is done one character at a time. Question 8 options: True False Question 9 (1 point) The Enigma machine is a is a stream cipher; encryption is done one character at a time. Question 9 options: True False Question 10 (1 point) The encryption key in a transposition cipher is (3, 2, 6, 1,