Mathematical methods of vector addition

Consider an airplane flying in still air at a velocity of 150 miles per hour northward.  In part 1 of the figure below, a 3-cm arrow represents this velocity.  Now a wind starts blowing toward the south east at a speed of 50 mi/hr-quite a wind!  The second part of the figure shows this 50-mi/hr wind.  In part 3, one arrow is moved so that its tail falls on the head of the other.  Assume that the angle between the two lines is 90⁰

Please find the results of the below statements

1. 1 cm = lb
2. The length of the wind vector in drawing (cm) =
3. Approximated net force in  (lb) =

A balloon is high enough that the sandbag hits the ground 2 seconds after it is released.  At that time the forward speed of the sandbag is still 12 m/s.  Its downward speed is now 19.6 m/s.

This drawing uses a scale of cm to represent m/s.  The arrow that shows the total is cm long, so the total velocity is m/s.