d. Itipu 18. For a loadbearing strength is the __ least loadbearing strength is the with the a. built-up lumber girder b. solid lumber girder c. LVL girder d. glulam girder 19. For a given total load, if the d. the streen its support columns is increased girder __ a. kan be decreased b. must be increased c. can remain the same d. must be decreased 120. Concrete joist systems allow thinner floor with high bearing capacities to be cre. ated. a. True b. False

18. The correct answer is **b. solid lumber girder**. Solid lumber girders generally have the least load-bearing strength compared to other types like built-up lumber, LVL (Laminated Veneer Lumber), and glulam (glued laminated timber) girders.<br /><br />19. The correct answer is **a. can be decreased**. If the distance between its support columns is increased for a given total load, the size of the girder can be decreased because the load is distributed over a longer span.<br /><br />20. The correct answer is **a. True**. Concrete joist systems allow for the creation of thinner floors with high bearing capacities due to their efficient design and material properties.