You use saber to describe a fact, information, or how to do something.
And you use conocer to say that you are familiar with something either a person, place, or thing.
Basically saber means to know of something, and conocer means to be familiar with someting.
HABIA
TENIA
CAMINABA
LLEVABA
ELABORADA
Sí, me gusta mucho está delicioso
Answer:
1. Nosotros abrimos los libros
Explanation:
In 1. abrimos is in the right form and tense
