I think that the correct answer would be 2.
The molecules in the air are always creating pressure. Countless molecules collide into everything every second, creating a constant force. Before the air in the balloon is heated, the molecules inside are creating as much pressure as the molecules outside, meaning that the balloon stays at equilibrium and neither expands nor contracts. When they get heated, however, the inside molecules start moving with more force. They create more pressure, causing the balloon to expand outward until the pressure equalizes.
How about to understand the nature of reality itself? Also, we live in the universe, so it might be useful to understand how it works.
Answer:
The families are thought to form as a result of collisions between asteroids. In many or most cases the parent body was shattered, but there are also several families which resulted from a large cratering event which did not disrupt the parent body (e.g. the Vesta, Pallas, Hygiea, and Massalia families).
The two factors are mass and distance between them.
Answer:
The velocity is 
Explanation:
From the question we are told that
The first distance is 
The first speed is 
The second distance is 
The second speed is 
Generally the time taken for first distance is
The time taken for second distance is
The total time is mathematically represented as
=> 
=> 
Generally the constant velocity that would let her finish at the same time is mathematically represented as
=> 
=>
