Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Ex Input:
Zero is the net force acting on an object when two equal forces are applied from opposite directions.

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


Ex Input:
Gastro-esophageal sphincter sphincter is located at the stomach end of the esophagus and opens to allow the bolus to enter the stomach.

Ex Output:
Which sphincter is located at the stomach end of the esophagus and opens to allow the bolus to enter the stomach?


Ex Input:
N and p pair of elements has the most similar properties.

Ex Output:

Which pair of elements has the most similar properties?