Help please am struggling so much

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

How would the number of moles (n) of o2 change if the atmospheric pressure doubled but all other variables stayed the same

Define a is a tiny pavket of energy