| 摘要 |
A protractor for measuring and constructing angles includes a body having a base member and an arcuate member connecting opposed ends of the base member. A bottom surface of the base member and a bottom surface of the arcuate member are disposed in a substantially identical plane. A degree scale is engageable with a predetermined portion of the arcuate member and an elongated arm has a first end rotatably attached to the base member and has a second end disposed in close proximity to the degree scale. A laser is attached to the second end of the elongated arm and is capable of generating a light beam.
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