I believe it’s B; Theories may be proven to be true and become laws.
A would make sense if we were talking about hypotheses however, we’re not.
Answer:
Force
Explanation:
The mass of an object is the quantity of matter it contains. It is measured in kilograms.
Acceleration is the ratio of the change in the velocity of an object to the change in time. It is measured in m/
.
When the mass of an object is multiplied with its acceleration, this gives the average force applied on the object. As force is defined as agent that can change the state of an object.
i.e F = m × a
where F is the force, m is the mass of the object and a its acceleration.
The two major classes of force are; contact force and field force.
Answer:
Part a)

Part b)

Part c)

Explanation:
Part a)
As we know that the friction force on two boxes is given as



Now we know by Newton's II law

so we have




Part b)
For block B we know that net force on it will push it forward with same acceleration so we have




Part c)
If Alex push from other side then also the acceleration will be same
So for box B we can say that Net force is given as




Answer:
"Why"
Explanation: A scientific law is a description of how the natural world behaves under certain circumstances.