Last one:)

plz help!

O2 is the answer buddy

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hope it helps:)

away from the curb

explanation:

the wheels would then hit the curb if it started to rolling, decreasing the chance of an accident.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.