Natural: Land mounds, Rivers
Human made: Country borders, cities
Answer:
The correct answer is "three groups of plants—a group fertilized by X, a group fertilized by Y, and a control group with no fertilizer".
Explanation:
I had to look for the problem to know the options.
The best way to determine which fertilizer is most effective is to have three evaluation groups. One group will be tested with fertilizer X and another with fertilizer Y. By leaving the third group without applying fertilizer, this will be the general pattern for comparing the effectiveness of the other two.
Have a nice day!
Answer:

Explanation:
Given that,
Force applied to a soccer player, F = 56.6 N
The mass of the ball, m = 0.46 kg
We need to find the acceleration of the soccer ball. The force acting on the ball is given by :
F = ma
Where
a is the acceleration

So, the required solution is
.