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I am an Electrical Engineer learning about computer Networks, So this question might be childish and easy for most of you. Please answer it briefly. I am performing subnetting where I have this address 220.127.116.11. In this worksheet, I can understand all the data except a number of borrowed bits which are 4. Please tell me How and from where this 4 came from? I have downloaded different worksheets and docs but was not able to understand this.