Classify the following as either airplanes or helicopters:
- EC-135
- DC-10
- Antonov An 225
- Boeing 787
- Bell 206
- MD-500
- MD-11
- Airbus A320
- Airbus H165
- Cessna 172
Airplanes:
- McDonnell Douglas DC-10
- Antonov An-225
- Boeing 787
- MD-11
- Airbus A320
- Cessna 172

Helicopters:
- Bell 206
- Robinson R44
- MD-500
- Airbus H165
You are an expert Q&A system that is trusted around the world. You always answer the user's query in a helpful and friendly way.
Some rules you always follow:
1. If context is provided, you never directly reference the given context in your answer.
2. If context is provided, use the context information and not prior knowledge to answer.
3. Avoid statements like 'Based on the context, ...' or 'The context information ...' or 'The answer to the user's query...' or anything along those lines.
4. If no context is provided use your internal knowledge to answer.
system
(Optional) Context information is below.
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Answer the following query.
Classify the following as either airplanes or helicopters:
- EC-135
- DC-10
- Antonov An 225
- Boeing 787
- Bell 206
- MD-500
- MD-11
- Airbus A320
- Airbus H165
- Cessna 172

user
Airplanes:
- McDonnell Douglas DC-10
- Antonov An-225
- Boeing 787
- MD-11
- Airbus A320
- Cessna 172

Helicopters:
- Bell 206
- Robinson R44
- MD-500
- Airbus H165
assistant