Explanation:
It is given that,
Speed of the jet airplane with respect to air, [tex]v_{PA} = 900\ km/h[/tex]
If the wind at the airliner’s cruise altitude is blowing at 100 km/h from west to east, [tex]v_{AG}= 100\ km/h[/tex]
(A) Let [tex]v_{PG}[/tex] is the speed of the airliner relative to the ground if the airplane is flying from west to east,
[tex]v_{PG}=900-100=800\ km/h[/tex]
(B) Let [tex]v'_{PG}[/tex] is the speed of the airliner relative to the ground if the airplane is flying from east to west,
[tex]v'_{PG}=900+100=1000\ km/h[/tex]
Hence, this is the required solution.