D-H public key exchange Please calculate the key for both Alice and Bob. 
 Alice Public area Bob 
 Alice and Bob publicly agree to make 
 N = 50, P = 41 
 Alice chooses her Bob 
 picks his 
 Private # A = 19 private # 
 B= ? 
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 I am on Alice site, I choose my private # A = 19. 
 You are on Bob site, you pick up the private B, B and N should have no common factor, except 1. 
 (Suggest to choose B as a prime #) Please calculate all the steps, and find the key made by Alice and Bob. 
 The ppt file of D-H cryptography is uploaded. You can follow the steps listed in the ppt file. 
 Show all steps.