A team of meteorologists is tracking the wind speed of an ocean cyclone. The plot at left in the DS-plane shows the relationship between the
km
wind speed, S, in kilometers per hour versus the distance from
h
the cyclone's center, D, in kilometers. The radius of maximum wind is
the distance from the cyclone's center to the point where the wind speed
is largest. According to the plot, who is the radius of maximum wind in
kilometers?