Nav Computer: Centre dot on TAS (197 kts), rotate to put wind direction (180šT) on HEADING index and mark wind on centre line 30kts below centre dot (over 167 kts).

Rotate to put track 240šT next to HEADING index; read drift (8š right (Stbd)) and rotate to put track (240š) under drift (8šStbd).  

On heading 232šT the drift 8šStbd will give the required track, 240šT and the groundspeed is under wind mark: 179 kts.       

39 nm at 179 kts = 13.0 minutes.

Aircraft descends through 18,000ft (FL220 – FL40)

18,000 feet in 13.0 minutes = 1,400 feet per minute.