Answer:
Option b. is correct.
Explanation:
In the given question a parachutist is falling toward the ground .
Also, the downward force of gravity is exactly equal to the upward force of air resistance.
So, net force applied to the parachutist is equal to zero ( because both force acts in opposite direction ).
Now by first law of motion :
An object will be in rest or in constant speed unless and until no external force is applied on it .
So, in the question the velocity of the parachutist is not changing with time.
Therefore, option b. is correct.
Hence, this is the required solution.
A. types or traits is the answer
A. 2 S O 2, gas, plus O 2, gas, in equilibrium with 2 S O 3, gas.