If an outburst of northern lights occurs 3.5 days after a large solar flare is seen, what is the average velocity of the solar wind? Give the answer in meters per second.
Divide the mean earth-sun distance (in meters) by the time delay (in seconds).
You will have to look up the distance (about 150 million km)and convert 3.5 days to seconds. Then do the dividing to get speed.