An airplane moves in straight level flight at constant velocity. What is the
net force acting on it if the mass of the plane is 1000 kg and the frictional
drag of the air is 1800 N? *

Net force = 0

Explanation:

We have, an airplane moves in straight level flight at constant velocity.

Mass of the plane is 1000 kg

The frictional force acting of the air is 1800 N.  

It is required to find the net force acting on it. We know that net force is given by the product of mass and acceleration. But here the airplane moves with constant speed, it means its acceleration is equal to 0 such that net force is equal to 0.

a and c

c is 100% but i am confused in a

show the wavelengths of a wave. show the crests of a wave.