Problem 1 (Affine Cipher): Alice read about the affine cipher. She liked that it had a bigger key space than the Caesar cipher. But, she thought it should be bigger still. Thus, she invented the double affine cipher. Here is how it works. Pick two affine cipher key pairs k1 = (1, 1) and k2 = (2, 2). Alices key is defined by the pair (k1, k2). Encrypt a plaintext letter m as Ek2(Ek1(m)), where Eki is the affine encryption function with key pair ki = (i, i), for i = 1, 2. 1. How large is Alices key space? 2. Suppose k1 = (7, 12) and k2 = (3, 8). What is Alices encryption of the letter D? Show