多选题 Your company makes compute-intensive, 3D rendering software for the movie industry. Your chief scientist has just discovered a new algorithm for several key methods in a commonly used utility class. The new algorithm will decrease processing time by 15 percent, without having to change any method signatures. After you change these key methods, and in the course of rigorous system testing, you discover that the changes have introduced no new bugs into the software.
In terms of your software"s overall design, which are probably true? (Choose all that apply.)