Wi-Fi Question:

Answer #1
★ Channel 1: 2.412 MHz
★ Channel 2: 2.417 MHz
★ Channel 3: 2.422 MHz
★ Channel 4: 2.427 MHz
★ Channel 5: 2.432 MHz
★ Channel 6: 2.437 MHz
You can choose from these channels while setting up the WLANs.

Answer #2
Only channels 1 6 11 should ever be used. Any other channel will bleed through.
Example Channel 1 will interfere with 2 and 3.

Answer #3
1, 6, 11