Why does this number not exactly match the atomic mass of 102.91 listed on the periodic table for this element?

What must occur for air masses to form fronts

Suppose that a certain fortunate person has a net worth of $71.0 billion ($7.10×1010). if her stock has a good year and gains $3.20 billion (3.20×109) in value, what is her new net worth?

The volume of an unknown substance in a sealed glass jar is 50 milliliters. the volume of the jar is 200 milliliters. which state of matter could the substance be?