The mass of a paper-clip is 0.50 g and the density of its material is 8.0g/cm'. The total volume of a number of clips is 20 cm.
How many paper-clips are there?

320 paper clips

Explanation:

mass = volume × density = 20cm³ × 8g/cm³ = 160g

mass of 1 paper clip = 0.50g

mass of x paper clips = 160g

x = 160/0.50 = 320

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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