Answer:
Commutative Property of Addition.
Step-by-step explanation:
The Commutative Property of Addition states that no matter what order you add the numbers, the outcome (answer) will all be the same.
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Answer:
5.39 units
Step-by-step explanation:
Pythagorean theorem: 
Let point (-2,1) be C
Line segment AC would be 2 units long.
Line segment BC would be 5 units long.
Insert the length of the line segments in to the Pythagorean theorem

4 + 25 = 29
≅ 5.385
Since the total of exterior angles of a plane figure is always 360, you would divide 360 by 20 which gives you 18
Answer: A. 90° clockwise, E. 270° counterclockwise