Answer:
Inhalation (via the respiratory tract)Absorption (via mucous membranes such as the eyes) Ingestion (via the gastrointestinal tract)
Explanation:
The opening where an infectious disease enters the host's body such as mucus membranes, open wounds, or tubes inserted in body cavities like urinary catheters or feeding tubes.
1)Straight chain hydrocarbons are named according to the number of carbon atoms: CH4, methane; C2H6 or H3C-CH3, ethane; C3H8 or H3C-CH2-CH3, propane; C4H10 or H3C-CH2- CH2-CH3, butane; C5H12 or CH3CH2CH2CH2CH3, pentane; C6H14 or CH3(CH2)4CH3, hexane; C7H16, heptane; C8H18, octane; C9H20, nonane; C10H22, CH3(CH2)8CH3, ..
14 sigma bonds, 1 pi bond