Terminal speed is the maximum speed that a falling object can reach and is based on aerodynamic resistance. In a vacuum, an object falling toward a planet as a result of gravity will continue to accelerate until it hits the ground.
However, if the object is falling through an atmosphere, such as on earth, then it will accelerate up to the point that the aerodynamic resistance cancels the downward force due to gravity, and it travels at a constant maximum speed, called the terminal velocity. At this point, resistance is equal to acceleration due to gravity. At terminal velocity, the skydiver's acceleration is zero.
Answeri believe it is the first one but not sure
Explanation:
52. It’s chemistry my dear^^^
What could people do to DECREASE erosion of the Earth’s surface?
Well, People can plant crops or they can grow plants and if your looking at the options only B and C has that, but lets make sure. So A) "Cut down more trees" does not help DECREASE erosion, if you want to decrease erosion then you have to have roots to make earth's surface stay. A is eliminated, going to B, B says "Use more land to plant crops." that's better because crops have roots so it can keep the surface/land sucked in and will not get erode away. Anyways moving on to C, C "Allow natural vegetation to grow." that kinda helps decrease erosion; so imma keep that in mind, and finally D "Allow cattle to graze more often." does not help at all. So D and A is eliminated, So theres only C and B left, C will kinda help but B will help more; So it will leave us to the final answer which is....
Answer: B) Use more land to plant crops.
I hope this helps you and I hope you understand what i'm talking about...
From The Special, Idk, my name is weired I just picked this name. I wish I could change it.
Answer:
b) No acceleration in the vertical
c) 35N
d) 35N
e) 
Explanation:
a) The situation can be shown in the free body diagram shown in the figure below where F is the applied force, Fr is the friction force, W is the weight of the book and N is the normal force exerted vertically up from the desk to the book
b) The vertical movement is restrained by the normal force which opposes to the weight. In absence of any other force, they both are in equilibrium and the net force is zero
c) The net horizontal force acting on the book is the vectorial sum of the applied force and the friction force. Since they lie in the same axis and are opposed to each other:

d) The net force acting on the book is the vector sum of all forces in all axes. The normal and the weight cancel each other in the y-axis, so our resulting force is the x-axis net force, computed as above:
in the x-axis
e) Following Newton's second law, the acceleration is calculated as
