Question

for a given depth, the type of floor truss that will span the greatest distance is a truss with what type of web? steel wood fiberglass perforated

Explanation:

Steel is a strong and durable material. In floor trusses, a steel - web truss can better handle the forces (such as tension and compression) over a greater span compared to wood (which has lower strength - to - weight ratio in some cases), fiberglass (which may not have the same load - bearing capacity as steel in this context), and perforated (which has holes that reduce its load - carrying ability).

Answer:

steel