order the topics from broadest to narrowest. broader how to grill a burger on a barbecue how to grill meats…

Brief Explanations:

The broader a topic, the more general it is. "How to grill meats on a barbecue" is the most general as it covers all types of meats. "How to grill a burger on a barbecue" is more specific as it focuses on just burgers. "How to grill a burger medium - rare" is the most specific as it not only focuses on burgers but also a specific doneness level.

Answer:

how to grill meats on a barbecue, how to grill a burger on a barbecue, how to grill a burger medium rare