Final answer:
The weather at KCOS is below approach minimums with a ceiling of 700 feet compared to the required 800 feet. However, KDEN meets its alternate minimums with the actual conditions being marginal, as the reported ceiling is at the minimum requirement.
Step-by-step explanation:
The question is asking whether the reported weather conditions at KCOS and KDEN meet or exceed the respective approach minimums for safe landing. Marginal weather in aviation refers to conditions that are above the minimum required for a particular approach procedure but not by much, implying limited and challenging flying conditions.
At KCOS, the reported weather is 1/2 statute mile visibility with light snow and an overcast ceiling at 700 feet AGL. The approach minimums for KCOS are 800 feet ceiling and 1/2 mile visibility. Since the ceiling is below minimums, this weather is considered below approach minimums, not marginal.
For the first alternate, KDEN, conditions are 2 statute miles visibility with an overcast ceiling at 400 feet AGL. The approach minimums for KDEN are 400 feet ceiling and 1 mile visibility. Here, the visibility is double the minimum but the ceiling is at the minimum, which is marginal but meets the required minimums for the approach.