Parallelism and Modifiers

[nagarjuna.kimidi]

Is this sentence parallel?
Trever collects stamps, old coins and flags.
Can one of the nouns in a parallel structure can have an adjective while the others dont?

Is there a fault with this sentence?
Obstinate and sturly, the manager's attitude irritated the employees.

The two words still describe the manager's attitude.

[jnelson0612]

Is this sentence parallel?
Trever collects stamps, old coins and flags.
Can one of the nouns in a parallel structure can have an adjective while the others dont?

Is there a fault with this sentence?
Obstinate and sturly, the manager's attitude irritated the employees.

The two words still describe the manager's attitude.

Your first sentence is just fine. They are all nouns, and "old" just tells what kind of coins he collects.

The second sentence is not correct. "obstinate" and "surly" are words that describe a person, not a person's attitude. The GMAT would believe that the modifying phrase at the beginning should describe "the manager".