The first end zone line, ususally referred to as the goal line.
0
The 50 yard line.
College football kicks off at the 35-yard line.
35 yard line
The 30 yard line.
40 yard line
30 yard line
The ball is placed at the 2 yard line in the NFL and the 3 yard line in college football.
The 20 yard line is considered the beginning of the Red Zone
The kicking teams 30 yard line.
It depends on the league and level of football, but in the NFL, the football is normally placed on the 2 yard line for both a point-after kick or a 2-point conversion attempt. In high school, it's placed on the 3 yard line. CFL rules put it on the 5 yard line.
one hundredth of a football field from touchdown line to touchdown line. A yard stick is a yard long.