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

[Q]: One gram of sugar or starch provides 4 calories of energy.
[A]: How many calories of energy does one gram of sugar or starch provide?


[Q]: The love canal tragedy was an infamous example of industrial waste dumping.
[A]: Love canal was an infamous example of what type of pollution?


[Q]: About about 2 km tall can mid-ocean ridges be.
[A]:
About how tall can mid-ocean ridges be?