No force is required to lift that balloon. In fact, force is required to hold it down, and if you let go, it's up, up, and away.
Since the balloon's density is less than the density of the air around it, it's lighter than the air it displaces, there is a net upward buoyant force acting on it, and it floats up !
Answer:
The positive end of battery 1 touching the negative end of battery 2 and wires connecting the negative of battery 1 to the light light bulb and the positive of battery 2 to the light bulb.
Explanation:
It should be 0.25kg because you converter from g to kg and since 1g<1kg so you move the decimal to the left