Another gas was used for many years to float transportation balloons.

which gas is it:

1) carbon dioxide
2) oxygen
3) hydrogen

why is this gas not used in balloons today?

What are transitions between a liquid and gas called? identify which way they are transitioning

2pos suppose an object in free fall is dropped from a building. its starting velocity is 0 m/s. ignoring the effects of air resistance, what is the speed (in m/s) of the object after falling 3 seconds? give your answer as a positive decimal without units. answer here

Displacement is the slope of a velocity vs. time graph a. true b. false