How many barium atoms are in a 9.8 × 10^-21 g sample?

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Chromosome 17 is made of over million base pairs.

4. a 20-kg child is tossed up into the air by her parent. the child is 2 meters off the ground traveling 5 m/s. circle one: ke / gpe / both show your work for finding the values of each type of energy the object has: