Suppose a ground-based observer in Question 35 measures the distance between the posts a...

Suppose a ground-based observer in Question 35 measures the distance between the posts at 100 meters. She then places exploding paint cans on the two posts and detonates them simultaneously as the train passes. An observer on the train then measures the distance between the paint splatters on the side of the train. Will his measurement be less than, equal to, or greater than 100 meters? Why?