yeungwk91

2) You may call it normal reaction in DSE or Upthrust

3) tangential acceleration is responsible for accelerating / decelerating.
    = rate of change of speed.

1) force is a vector definitely.
the magnitude of force is a scalar.

The Q asks for final velocity => it means the magnitude of velocity

yeungwk91

It is about fluid mechanics

The force should be called Upthrust.
It is acting on the plane by the air surrounding.

Just for DSE, u mark it as normal reaction ( that's fine)