. An air-traffic controller observes two aircraft on his

radar screen. The first is at altitude 800 m, horizontal

distance 19.2 km, and 25.0° south of west. The second

aircraft is at altitude 1

100 m, horizontal distance

17.6 km, and 20.0° south of west. What is the distance

between the two aircraft? (Place the

x

axis west, the

y

axis south, and the

z

axis vertical​