Predicate Logic

Three questions that need clarifications.

"Every walker loves some talker" has two disambiguations. Find forms for both and draw two trees to check if either form is a contradiction. The trees are:
both infinite.
both open.
both closed.
both finite.

I think they should be both open. Any opinions?

"Everything is something" has:
a false disambiguation.
a contradictory disambiguation.
a true disambiguation.
a tautologous disambiguation.

I have totally no idea on this. Need clarification on this question

Identity is reflexive, symmetric and transitive. Marriage is obviously not reflexive, but if it is monogamous then:
it is transitive but not symmetric.
it is not symmetric or transitive.
it is symmetric but not transitive.
it is symmetric and transitive.

I suggested that the answer should be 'it is symmetric but not transitive' as 'a is married to b and b is married to a (symmetric), but it cannot be the case that a is married to b, and b married to c, thus a is married to c which. This suggest it is not transitive. Comments and clarifications appreciated! Thanks.