Pj likes to ride his bike around the block. if he rides out of his house west, the sidewalk circles his block, and brings him back to his doorstep 0.35 miles later. find his distance and displacement.

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.

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)