Answer:
180 miles/ 3 hours
Explanation:
180 miles / 3 hours is the same as 60 miles per hour
240 miles /6 hours is the same as 45 miles per hour
90 miles / 2 hours is the same as 45 miles per hour as well
and 30 miles per hour just stays like that.
Therefore, 180 miles per 3 hours is the correct answer