Between which two pints does the object have the greatest speed please help

Can someone me with questions 12 and 13 plz.

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

The sum of the oxidation numbers in a neutral compound is always