a 500.-kg Tower of Terror coaster starts at rest at the top of a 90.0 Tower at what speed would it hit the ground of had no brakes

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?

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The comparison of the number of atoms in a copper coin the size of a penny with the number of people on earth is made to illustrate which of the following? a. that atoms are indivisible b. that atoms are very small c. that atoms are very large d. that in a copper penny, there is one atom for every person on earth