Round trip. An airplane flies from Chicago to New Orleans (a distance of 1500 km) in the morning and then immediately returns to Chicago. The airplane’s speed relative to the air is 250 m/s. The wind is blowing at 50 m/s from west to east, so it is perpendicular to the line that connects the two cities. 

(a) What is the average speed of the airplane relative to the ground on the way to New Orleans? 

(b) What is the average speed relative to the ground on the way back to Chicago? 

(c) What is the average speed for the entire trip?