Please help, 5 pnts .

The double bond between a carbon atom and two oxygen atoms (a molecule of carbon dioxide) has two characteristics. what are they? a. an ionic bond is formed between the oxygen and carbon atoms. b. four valence electrons are shared. c. two valence electrons are shared. d. valence electrons are shared between oxygen atoms.

Natural selection changes allele frequencies because some survive and reproduce more successfully than others.

Based on her survey, which advertising mediums will work best to publicize leslie's in-store specials?