The answer is A. Commensalism. <span>Commensalism, in ecology, is a class of relationships between two organisms where one organism benefits from the other without affecting it. This was the briefest answer from Wiki. Hope it helps, and sorry I'm late.</span>
To solve this exercise it is necessary to apply the concepts related to Robert Boyle's law where:

Where,
P = Pressure
V = Volume
T = Temperature
n = amount of substance
R = Ideal gas constant
We start by calculating the volume of inhaled O_2 for it:


Our values are given as
P = 1atm
T=293K 
Using the equation to find n, we have:




Number of molecules would be found through Avogadro number, then


Answer:
D because those are both concerning.
Gravity is the force that attracts all matter to each other.
Explanation:
Sir Isaac Newton discovered Gravity when he saw a falling apple while thinking about the forces of nature.
Gravity is a fundamental force that causes objects to have weight. Gravity acts on all matter and is a function of both mass and distance. Each object attracts every other object with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between them. The force of attraction is, however, negligible between most objects because of their small size.
Gravitational force is given as:

Where G is gravitational constant and is equal to 6.674×10−11 m³⋅kg⁻¹⋅s⁻²
m₁ and m₂ are the masses of the two objects.
r is the distance between the two objects.
The gravity is what makes an apple fall on the ground and gravity is the force that keeps us on the ground.
Keywords: gravity, Newton, Force, weight
Learn more about gravitational force from brainly.com/question/14321566
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Answer:a. 24 kg m/s
b. 3/5s
Explanation:
a.impulse is the change in momentum so at first the momentum is zero because the ball was at rest and the final momentum is 1.2kg*20m/s=24 kg m/s
so the impulse would be (24-0) kg m/s=24 kg m/s
b. so the impulse equation is impulse is force *delts time
so 24 kg m/s=40N*t
t=24 kg m/s /40N=3/5 s