Which of the following filters would be appropriate for a large industrial air handler?

Which of the following filters would be appropriate for a large industrial air handler?
 
  A) a 16  20  1 panel filter B) an electronic air cleaner
  C) a large fiberglass roll filter D) a washable hogs hair filter

 Q. 2

Why should ultraviolet germicidal lamps not be handled with bare hands?
 
  A) The coating on the outside of the lamps is toxic
  B) The oil from your fingerprints can lead to premature failure of the lamp
  C) The exterior UV coating will wipe off, reducing the UV output
  D) The residual UV in the lamp coatings can cause severe burns