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Author Question: What is the marginal cost of producing the third unit? a. 60 b. 70 c. 90 d. ... (Read 18 times) |
A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.
Vampire bats have a natural anticoagulant in their saliva that permits continuous bleeding after they painlessly open a wound with their incisors. This capillary blood does not cause any significant blood loss to their victims.
Throughout history, plants containing cardiac steroids have been used as heart drugs and as poisons (e.g., in arrows used in combat), emetics, and diuretics.
Earwax has antimicrobial properties that reduce the viability of bacteria and fungus in the human ear.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.