Answer:
1. A cipher key is created by performing a binary divide (modulo 2). For these values, work out cipher key: 10100, 1000
Additional information:
GF(2) - Galois field of two elements - is used in many areas including with Checksums and Ciphers. It basically involves some bit shifts and an EX-OR function, which makes it fast in computing the multiplication. For example 10010 รท 11 gives: 1110 ------- 11 | 10010 11 ------ 1010 11 ----- 110 11 --- 00
Ans: 10