unknown-track - Race 4

Across the Board

Refers to betting on a horse to finish first, second, and third to cover any of those scenarios happening during a race

Scratch

A horse is a scratch when injury or other necessity causes it to be withdrawn from the race.

Pari-Mutuel

A pool style wagering system, where all money input through betting is divided among those with winning tickets (save for various deductions by the track operators).