a) Design a LSFR with using x4 + x + 1 characteristic polynomial and find the key sequence to generate for the initial value: (1010) b) Design a LSFR which uses x + x4 + x + x + 1 primitive polynomial as characteristic polynomial and find period. a) Design a LSFR with using x4 + x + 1 characteristic polynomial and find the key sequence to generate for the initial value: (1010) b) Design a LSFR which uses x + x4 + x + x + 1 primitive polynomial as characteristic polynomial and find period