Answer: Jada is fastest.
Explanation:
Jada is going at a higher speed because going 2 miles compared to 1 mile is longer but also 2 miles in 12 minutes compared to 1 mile in 24 minutes, it took longer for Jada's cousin to get to that point which means in conclusion Jada is faster.
(2 miles, 12 minutes > 1 mile, 24 minutes)