This Instructional Activity is a part of the Lesson 26, Unit 6, Grade 7. Find the volume of the right prism shown in the diagram whose base is the region between two right triangles. Use two different strategies. Strategy 1: The volume of the right prism is equal to the difference of the volumes of the two triangular prisms. Strategy 2: The volume of a right prism is equal to the area of its base times its height.