Answer
Con el poco texto que nos das podemos deducir que es la contaminación marina.
Answer:
We have homework in class. (little)
Explanation:
Tenemos is the nosotros form of tener. so you could say "nosotros tenemos" but "tenemos" works because tenemos is the only way to say the verb tener in the nosotros form so people get what you mean when you just say tenemos
The answer might be 3) repite
