exchange.cornell.edu SPF records

SPF
5m
"v=spf1 ip4:128.253.150.144/30 ?all"

Question and response

Question

dig exchange.cornell.edu. SPF

Answer

exchange.cornell.edu. 300 SPF "v=spf1 ip4:128.253.150.144/30 ?all"

Authority

The response has no authority records.

Additional

. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0