Answer:
Olga
Step-by-step explanation:
To calculate average speed we can compare their hourly rate
Trisha ran 10km in 2.5 hours which is equal to 4km in an hour
Jason ran 7.5km in 2 hours which is equal to 3.75km an hour
Olga ran 9.5km in 2.25 hours which is equal to 4.2 an hour approximately
