1) Given the 8-bit twos complement numbers A = 0110 1000, and B = 0101 1010, compute B in twos complement, and then compute A B by adding A and B in twos complement. Answer all the following: Determine: B = Compute: A B = Is there an overflow, and why? What is the value of the answer in decimal?

2) Compute the value of the following modular expression using modulo reduction. Your answer must be a specific mod 17 number, not a formula or expression of any kind. Show your work. 323 mod 17 =

3) Encrypt the message: blankspace using the Vigenre cipher with the key DANGER. Plaintext alphabet:

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

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