Has the MAC address been changed?

Question

Computer networks

Hello, please help me figure it out.
I can not understand which MAC addresses are protected by the vendor, and which ones are manually set.
It's just about theory.
Here are a few poppies, let's say:
1.B8-97-5A-29-27-3D
2.06-00-00-00-00-00
3.00-50-B6-5B-CA-6A
To find out if it has been changed administratively or no need: 27, 00, CA to convert from hexadecimal to 2-decimal and look at the 2nd character - is it 0 or 1?
Thus:
1. Not changed
2. Not changed
3. Changed

Answer 1

What exactly is the problem?
B8 ₁₆ = 101110 0 0 ₂ - global