Here are the answers to the questions you've provided:
Question 3: Which of these activities are you most likely to do in el banco?
The correct response is: cobrar un cheque. (This means "cash a check," which is a common activity in a bank.)
Question 4: To which of the following nouns can "lo" refer in the sentence "Lo comí."?
The correct response is: el pan. (In this case, "lo" refers to a masculine singular noun, and "el pan" is the only option that fits.)
Question 5: Nosotros _________ al centro de Bogotá ayer.
The correct response is: fuimos. (This is the first-person plural form of the verb "ir" in the preterite tense, which is appropriate for indicating an action that occurred yesterday.)
Let me know if you have any more questions!