Answer:
6m²
Step-by-step explanation:
Because the question asks for the area of a face but it doesn't indicate which face then it can be any of the faces.
2m x 3m = 6m²
2m x 4m = 8m²
3m x 4m = 12m²
In your case one of the possible answers is 6m² - so that is the one they are looking for.
