To convert hexadecimal to binary one must first convert each hexadecimal digit to 4 binary digits.In our case hexadecimal B into binary digit is 1011 whereas 2 is 0010.So B2 would be 1011 0010.
Hexadecimal number system uses 10 digits and 6 letter. B being one of the letter is equal to 11. 11 interpreted in counting digits is 1011. while 2 in counting digit is 0010. Thus hexadecimal B2 to binary is 10110010