I think it’s “All day we unpacked boxes, filled cupboards” because the first one doesn’t have anything to do with determination, the second one doesn’t fit determination either, and the last one doesn’t fit either. The third one fits because doing something ALL day would be determination I’m pretty sure.
The sentence needs commas because the participial phrase is essential.
Answer:
It is third person point of view.
Explanation:
The narrator refers to the main character, Marvin, using the pronoun "he." This makes it a third-person point of view.