A number should be rounded up if? it is the first digit, the number after it is between 0 and 4, the number after is between 5 and 9, it is the last digit

How many moles of magnesium is 3.01 x10^22 atoms of magnesium?

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

What happened to the amount of carbon dioxide in the atmosphere from 2010–2017?