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If we encrypt the message 0xAF C0 4D using the one-time pad and key 0xC9 2B 39. What is the resulting ciphertext?

Which of the following is a setting in which a pseudorandom generator could be applied?

What is the size of key space |K| for a shift cipher, considering the message space as English alphabets, and encryption algorithm as Enc​(m)=(m+shift)mod 26?

What is the value (in decimal) of 0x48?

Which of the following problems is hard if the RSA assumption holds? In all the below, N is a product of distinct, large primes p and q, and e is relatively prime to ϕ(N).

Let G be a function mapping n-bit inputs to 2n-bit outputs. Which of the following is true of the pseudo one-time pad encryption scheme based on G?

What is the size of key space |K| for a byte-wise shift cipher, considering the message space as English alphabets, and encryption algorithm as Enc​(m)=(m⊕k)?

In which of the following settings is naive application of private-key cryptography applicable? (Check all that apply.)

3-1 mod 7 = ? Alternatively, what is the inverse of 3 mod 7 on multiplication?

Assume we want to use a hash function with output length as small as possible, subject to being collision resistant against a birthday attack running in time 2192. Which hash function would be the best choice?