Give an example of how a transition piece isused in industry.

Mr. Smith _____heavily, but he has given it up. A: usestosmoke B: used tosmoke C: isused to D: was asked to

What is the term for the space that exists above a drop ceiling or below a raised floor and that isused for air return？（） A: NEMA area B: plenum area C: DAS area D: extended area E: RF special area