Based on your observations from the Can Crush Lab, why would a helium balloon that rises into the atmosphere eventually burst? Atmospheric pressure outside the balloon increases as the balloon rises.
Atmospheric pressure outside the balloon decreases as the balloon rises.
Helium molecules inside the balloon decrease as the balloon rises.
Helium molecules inside the balloon increase as the balloon rises.

Outside of the balloon, air increasing pressure even as balloon grows.

Explanation:

The volume of the air increased with increase in ambient height, meaning that the amount of air molecules per unit area decreases. The pressure placed by the air is therefore decreased due to this decrease in air density.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.