If you would like to know how much will you pay for 2 feet, you can calculate this using the following steps:
1 yard equals to 3 feet
1 yard for $12.99:
3 feet ... $12.99
2 feet ... $x = ?
3 * x = 2 * 12.99 /3
x = 2 * 12.99 / 3
x = $8.66
The correct result would be $8.66.