How is 2/8 of the sky covered by smoke at 2,500 feet AGL encoded in column 10?

The encoding "FEW025" is appropriate for indicating that a small portion of the sky is covered at a specific altitude. In aviation weather reports, "FEW" signifies that there are few clouds, and in this case, it also conveys that 2/8 of the sky is covered by smoke, which can be treated similarly to cloud coverage for reporting purposes.

The number "025" indicates the altitude at which this coverage occurs, specifically 2,500 feet above ground level (AGL). This level of detail is crucial for pilots and meteorologists who need to understand atmospheric conditions at different altitudes.

In contrast, the other options would represent different conditions. "BKN" indicates a broken cloud layer, "OVC" signals overcast conditions, and "SCT" refers to scattered clouds, none of which accurately reflect the condition of 2/8 sky coverage. Hence, "FEW025" clearly describes the scenario presented in the question.