TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Zero is the net force acting on an object when two equal forces are applied from opposite directions.

SOLUTION: What is the net force acting on an object when two equal forces are applied from opposite directions?

PROBLEM: The bird ancestor that lived in trees developed wings, which is commonly associated with birds.

SOLUTION: The bird ancestor that lived in trees developed what feature commonly associated with birds?

PROBLEM: Chemists use simple diagrams to show an atom’s valence electrons and how they do transfer.

SOLUTION:
Chemists use simple diagrams to show an atom’s valence electrons and how they do what?