1) It would be "fue interesante" because of the subject IT.
Fui: I was
Fuiste: you were
Fueron: they were.
2) Farmacias in a Spanish- speaking country (like Colombia) is moving forward the U.S style. This is because the focus on selling just medicines, drugs and in the U.S drugstore you might find more than just medical elements.
3) In Los Novios park you can rent a boat (option C). You can enjoy one of its main attraction which is the lake where you can find ducks and fish, and you might rent a boat, bike or a kayak.