Answer:
W18 * 106
Explanation:
Given that the section modulus of the wide flange beam is 200 in^3 the lightest beam possible that can satisfy the section modulus must have a section modulus ≥ 200 in^3. also the value of the section modulus must be approximately closest to 200in^3
From wide flange Beam table ( showing the section modulus )
The beam that can satisfy the condition is W18 × 106 because its section modulus ( s ) = 204 in^3
