Interpret the arrangement of the periodic table to explain how properties are used to classify elements, including periods and groups.

Add the fractions, and simply the result to lowest terms. 2/3 + 2/7= ?

The diagonals of a quadrilaretral intersect at (-1,4). one of the sides of the quadrilateral is bounded by (2,7) and (-3,5) determine the coordinates of the other side in order for the quadrilaretral to be a square.

Opposite angles in a parrellelogram are