11. Describe the difference between beams and columns. __ 12. Describe the difference between a strut and a tie. __ __ 13. A(n) __ is the device that connects two or more structural members together. __ 14. A typical structure that is used to support a roof is known as a(n) __ 15. Determine if a truss with 8 joints and 15 members is stable. Explain why or why not. __ __ 16. Which type of bridge is used to span short distances? A. Beam B. Cantilever C. Suspension D. Arch __ 17. Which of the following bridges is used in the world's longest bridges? A. Bcam B. Cantilever C. Suspension D. Arch __ 18. A reinforced concrete shaft at the center of a skyscraper is known as a(n) __ __ 19. Land surveying is a branch of __ engineering. __ 20. The largest employer of civil engineers is the __

## Step1<br />Beams and columns are both structural elements, but they have different roles. Beams are horizontal structural elements that primarily resist loads applied laterally to their axis. They are designed to carry loads that are perpendicular to their length. On the other hand, columns are vertical structural elements that primarily resist loads applied axially. They are designed to carry loads that are parallel to their length.<br /><br />## Step2<br />A strut and a tie are both structural elements, but they have different roles. A strut is a structural member that is designed to resist axial compression. It is used to support loads that are pushing inwards. A tie, on the other hand, is a structural member that is designed to resist axial tension. It is used to support loads that are pulling outwards.<br /><br />## Step3<br />A connector is a device that connects two or more structural members together. It is used to ensure that the structural members are securely joined together and can work as a single unit.<br /><br />## Step4<br />A typical structure that is used to support a roof is known as a truss. A truss is a framework, typically consisting of rafters, posts, and struts, that supports a roof.<br /><br />## Step5<br />A truss with 8 joints and 15 members is stable. This is because a truss with 8 joints and 15 members satisfies the condition of Euler's formula for planar graphs, which states that the number of faces (F) minus the number of vertices (V) plus the number of edges (E) equals 2 (F - V + E = 2). This formula is used to determine the planarity of a graph.<br /><br />## Step6<br />A beam bridge is used to span short distances. It is a simple and efficient way to span short distances, as it requires less material and is easier to construct.<br /><br />## Step7<br />Suspension bridges are used in the world's longest bridges. They are designed to span long distances and are capable of carrying heavy loads.<br /><br />## Step8<br />A reinforced concrete shaft at the center of a skyscraper is known as a core. The core is the central part of the building and is designed to carry the weight of the building and its occupants.<br /><br />## Step9<br />Land surveying is a branch of civil engineering. It involves the measurement and mapping of the Earth's surface, and is used to create accurate maps and plans for construction projects.<br /><br />## Step10<br />The largest employer of civil engineers is the construction industry. Civil engineers are responsible for designing and overseeing the construction of infrastructure projects, such as roads, bridges, and buildings.