You will be given a definition of a task first, then some input of the task.
You are given a passage. You need to construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) its answer is the whole paragraph. Avoid creating questions that can be answered correctly without actually understanding the paragraph.

If you start a fire in zero gravity then (as long as it is not against the wall of the space craft) it will burn as a sphere. The fire needs oxygen so will expand, however, as it expands more heat is lost, and the fire may go out.

So it would be a hot, glowing sphere that expands and then goes out.

Of course if it is contact with the wall or something then the nature of the fire depend on the fuels available, etc.
Output:
How do fire act in 'zero gravity'?