Mini Project In Air Conditioning

Hello,

please suggest me a topic to select for my mini project in air conditioning.
post-selection of topic, how to prepare a report, what are the key points to be considered. how many pages the report should be limited to?

I am in a dillema as to which topic is to be selected from these:
1. chilled beams
2. Terminal fan unit
3. diffusers
4. dampers
The company in which i am doing my project is a manufacturing unit of airconditioning components.
should i choose manufacturing or design.. which one would be beneficial to me. I am a mechanical engineering student.