Answer:
The argument is valid.
Explanation:
We are told "Loretta's hobby is stamp collecting."
"If her husband likes to fish, then Loretta's hobby is not stamp collecting."
Her hobby is stamp collecting, so her husband does not like to fish.
"If her husband does not like to fish, then Nathan likes to read."
Her husband does not like to fish; therefore, Nathan likes to read.
The argument is valid.