About disk ZCS/BCS question

I have serveral questions about disk want to ask.



What is the advantage of using a 520-byte sector on a disk than a 512-byte sector?
Can I use 512-bytes sector disk and 520-bytes sector disk in the same raid group?


ZCS is use the ninth block to checksum.
BCS is use the Sixtieth-four block to checksum.
After the raid group is created.
Can I understand the raid group have double checksum ?
BCS/ZCS and checksum disk.


How BCS/ZCS work?