Spelling U4W1A

3. be entitled or appointed to act or speak for (someone), especially in an official capacity.
5. relating to or expressed as a number or numbers.
12. made up of exactly similar parts facing each other or around an axis; showing symmetry.
13. able to be changed or adapted.
15. a regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points (the foci) is constant, or resulting when a cone is cut by an oblique plane which does not intersect the base.
18. a thorough or dramatic change in form or appearance.
19. of or denoting circles, arcs, or other shapes which share the same center, the larger often completely surrounding the smaller.
20. short for ordinal number.

1. completing or enhancing something.
2. of or involving the action of associating ideas or things.
4. the number below the line in a common fraction; a divisor.
6. having two sides of equal length.
7. following continuously.
8. involving the condition that a group of quantities connected by operators gives the same result whatever the order of the quantities involved.
9. an instrument for measuring angles, typically in the form of a flat semicircle marked with degrees along the curved edge.
10. the least or smallest amount or quantity possible, attainable, or required.
11. an arrangement of shapes closely fitted together, especially of polygons in a repeated pattern without gaps or overlapping.
14. difference in size, degree, circumstances, etc.; lack of equality.
16. a metric unit of measurement for mass or weight that is equal to 1/10 of a gram
17. denoting or relating to a value or quantity lying at the midpoint of a frequency distribution of observed values or quantities, such that there is an equal probability of falling above or below it.