Use Domain-Specific Vocabulary

Read the passage.
Clams and oysters are bivalves, water animals with hinged shells. On the outside of the bivalve’s soft body is a thin mantle. This mantle secretes the two valves, or shell halves. In the place where the valves meet, they are joined by hinge teeth, large bumps on both shell halves that help them stay aligned to one another. The valves are held together by a ligament, a dark, fleshy part of the bivalve attached to both shell halves at the hinge.
Complete the sentence with the correct term.

Read the passage.
Various tools can be used to measure and draw angles precisely. The most familiar tool is the protractor, a clear plastic circle or semicircle with degrees marked along its arch. Less familiar is the goniometer, which has two arms that are moved to the correct position relative to one another to measure or draw an angle. Set squares are clear plastic triangles with common angles, such as 45°, 60°, or 90°. The user places the set square on a surface and then traces the shape of whichever angle is desired. Additionally, with some mathematical knowledge, a compass can be used to measure degrees and draw precise angles.
Label the image with the correct term.