After school, Maya and Naomi headed to the beach, 6 miles away

After school, Maya and Naomi headed to the beach, 6 miles away

After school, Maya and Naomi headed to the beach, 6 miles away. Maya decided to bike while Naomi took a bus. The graph below shows their journeys, indicating the time and distance traveled. What was the difference, in miles per hour, between Naomi’s and Maya’s average speeds?

(A) 6 (B) 12 (C) 18 (D) 20 (E) 24

answer：E