Computer-aided design of these structures can use a LUSAS (“lusas”) software package named for them. James Warren is best known for patenting a ubiquitous design of these structures. Arup added 89 dampers to one of these structures (-5[1])after synchronous lateral excitation (10[1])caused its 2000 opening (10[1])to be pushed back. Aeroelastic (10[1]-5[1])flutter, not resonance as commonly believed, was the cause (10[1])of the 1940 rupture (10[1])of one of these structures (-5[1])in Tacoma. A triangular truss (10[1])is often (10[1])used in these structures to mitigate buckling. (10[1])Unlike in a viaduct, a catenary is formed by the cable that supports the deck of the suspension type of these structures. For 10 points, name these structures that span a river. ■END■ (10[1])