Final answer:
A 2x4 is a type of natural lumber used in construction, made from solid wood obtained by cutting and processing logs. Manufactured lumber refers to engineered wood products like plywood or particleboard, which are made by bonding wood veneers or particles together.
Step-by-step explanation:
A 2x4 is a type of natural lumber used in construction. It is made from solid wood, typically spruce, pine, or fir. Natural lumber is obtained by cutting and processing logs into various sizes and shapes. In contrast, manufactured lumber refers to engineered wood products like plywood or particleboard, which are made by bonding wood veneers or particles together.