The FMA indicates what system is controlling the aircraft and what mode is operational.

1st segment starts at screen height and finishes at gear retracted.

2nd segment starts when the gear is retracted and finishes when acceleration alt is reached (min. 400ft max 1000ft) speed V2.

3rd segment starts at acceleration alt, minimum 400ft, and finishes when the flaps are retracted.

4th segment starts when the flaps are retracted, MCT is set and finishes at the 1500ft.

The distance from the datum to the point at which the weight of a component acts.

The Boeing 737 has an all moving horizontal stabilizer.

Minimum decent altitude (non-precision), the lowest altitude, expressed in feet above mean sea level to which descent is authorised on final approach or during circle-to-land maneuvering in execution of a standard instrument approach procedure where no electronic glideslope is provided.

If not visual between MDA and MAPt, a Go-around must be initiated.

Stall speed is defined as the minimum steady flight speed at which the airplane is controllable.

At the tip as downwash and spanwise flow effect the angle of attack at each section, but because of the tapered wing the effective angle of attack near the tips is greater than that near the center.

V1 is the decision speed (sometimes referred to as critical engine speed or critical engine failure speed) by which any decision to reject a takeoff must be made.

V2 is the takeoff safety speed which must be attained at the 35 ft height at the end of the required runway distance. This is essentially the best one-engine inoperative angle of climb speed for the airplane and is a minimum speed for flight in that condition until at least 400 ft above the ground. V2 shall be at least 1.1 times VMCA, and no less than 1.2 times VS.

Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.

VMCA is the minimum control speed in the air and is defined as the minimum speed, whilst in the air, that directional control can be maintained with one engine inoperative (critical engine on two engine aerolanes), operating engine(s) at takeoff power and a maximum of 5 degrees of bank towards the good engine(s).

VMCG is the minimum control speed on the ground and is defined as the minimum speed, whilst on the ground, that directional control can be maintained, using only aerodynamic controls, with one engine inoperative (critical engine on two engine airplanes) and takeoff power applied on the other engine(s).

NDB’s are stations emitting a signal. There is nothing for them to be accurate about. ADF's on the other hand, when tuned to an NDB need to be accurate within +/- 5 degrees.

To increase the strength of the surfaces.

The same strategy is employed by plastic water bottles, by adding ridges to a surface you increase it's structural rigidity