What is a sprint in the tour de France?

Answer 1

It's a specially posted sub-section of the stage, with a beginning and an end. Out of those riders who reach the beginning of the sprint section together, the one who is first to the end will get the points for that sprint.

After the end of the sprint section, the stage will continue.

A solo rider ahead of the pack won't get any sprint points, even if he is first through the sprint section.

Answer 2

Unlikely.

The overall winners tend to be fairly all-round riders, with a hint of being good climbers.