Which of these addresses is NOT in an RFC 1918 private range?

172.32.0.1 is not private. RFC 1918 defines three private ranges:
• 10.0.0.0/8
• 172.16.0.0/12
• 192.168.0.0/16

The /12 range only covers 172.16.0.0 to 172.31.255.255. So 172.32.0.1 is a public address, while 172.20.0.5 is private. Many people wrongly think every 172.x address is private.