Which trail is longer? how much longer is it in miles and yards? show your work.

I've managed to read the visual. Next time post a better visual that is not very blurry. Moving on to the problem.
First you must know that 1 mile = 1760 yards.
Dominic's trail is 6 miles long, which is equal to 10560 yards. 
You can compare Dominic's trail, 10560, to Terell's trail, 7020.
10560 > 7020

Therefore, Dominic's trail is longer.<

To find the difference, subtract.
10560 - 7020 = 3540

In yards, the difference is 3540.<

3540 yards is the same as 2.01.

2.01 is the difference .<

Answers include the arrow. <