An airplane starts from A and flies to B at a constant speed. After reaching B it returns to A at the same speed. There was no wind. Assuming there was a wind from A to B of constant magnitude, when will the round trip take more time – when there is a wind or when there is no wind? Assume that the wind speed is less than that of the plane.
1. Longer round trip time when there is a constant wind.
2. More information is needed.
3. The same time in both cases.
4. Longer round trip time when there is no wind.