Answer:
8.1 units
Explanation:
The horizontal distance is 6-2 = 4 units.
The vertical distance is 8-1 = 7 units.
The distance from S to U must be more than 7 units and less than 7+4 = 11 units. There is only one answer choice in this range:
8.1 units
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Additional comment
If you want to figure the distance, it is the hypotenuse of a right triangle with legs 4 and 7. The Pythagorean theorem tells you that distance is ...
SU² = 4² +7² = 16 +49 = 65
SU = √65 ≈ 8.062 ≈ 8.1