Anchor: One plausible reason is that the differences are the result of how states solicit returns, monitor compliance, and penalize failure to file.
Entailed: The differences are a result of how the state solicits returns.
Contradiction: There are no reasons why there are differences. 
Contradiction: The function they performed for me was insignificant.
Contradiction: There is a bike flying through the air.
Contradiction: Over the course of time the building seemed to loom.
Contradiction: A child and a woman are relaxing in front of the tree at christmas.