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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?

Question 8 (2 points) Assume that I saw all the mobility data in class and I watched the presentation of Chetty et al’s work on social capital that we also saw in class, and that I summarized it as saying that kids that grow up in single-parent households have less upward-mobility than do kids that grow up in two-parent households. Based on the material from class, what is not right about that statement? What might have some truth to it? Teach it to me, making reference to material from class.

Question 4 (2 points) How do Acemoglu et al measure the way technological innovation impacts the “task content” of production? Teach this to me, making sure to define terms, in a way that summarizes this research.