Hurry i need a) under what circumstances might a very precise measurement not be accurate? explainb) are the any circumstances which an accurate measurement may not be precise? explainc) i measured the length of my thumb and found that it s 7.50 centimeters long. when i used another ruler i found that the length was 7.5 centimeters. explain the difference between these two measuirements

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

What the blanks in these lines are ?

The image compares the arrangement of electrons in two different neutral atoms. a figure labeled atom q has a shaded sphere at the center of three concentric circles. the innermost circle has two black spheres. the middle circle has six black spheres. to the left of this figure is another figure labeled atom p. atom p has a shaded sphere at the center of three concentric circles. the innermost circle has two black spheres. the middle circle has seven black spheres. which of the following best explains the position of the two atoms in the periodic table?