* Net Force: The net force is the overall force acting on an object. In this case, the net force is acting vertically upward.

* Acceleration: Acceleration is the change in velocity over time. It always occurs in the direction of the net force.

Therefore, the balloon would accelerate upwards, even though it's being blown westward.

Here's why:

* The westward force from the wind is only affecting the balloon's horizontal motion. It's not changing the balloon's vertical motion.

* The upward net force is the dominant force, causing the balloon to accelerate upwards.

Think of it like this: Imagine pushing a box horizontally while someone else is pulling it vertically upwards. The box will move upwards, even though you're pushing it sideways.