Q1: When 1100010 is divided by 0101, what will be the decimal remainder?

ANS:B - 3

This question is solved by the method of binary to decimal conversion.
i.e. Binary has a base 2 and to convert it to decimal, please follow the method.

Suppose 110100 would be like
1*(2^6) + !*(2^5) + 0*(2^4) + 0*(2^3) + 1*(2^1) + 0*(2^0) = 98.
From right to left raise the power like 2 raised to 0 then 2 raised to 1 etc.
Similarly 0101=5.
98/5 leaves us a remainder 3.
So the answer is 3.