Official websites use .gov
A
.gov website belongs to an official
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A lock (
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connected to the .gov website. Share sensitive
information only on official, secure websites.
(A) Yellow filter vs. blue filter, (B) Yellow and UV filter vs. blue filter, (C) Yellow and UV filter vs. blue and UV filter, (D) Clear filter vs. clear with blue filter. Different letters above columns indicate significant differences (P < 0.05).
