Every Year the Common Flu Vaccine Is Designed to Protect

question 27

Multiple Choice

Every year the common flu vaccine is designed to protect against three different strains of the influenza virus.Why do scientists typically have to make a new vaccine every year?

• A) Our bodies develop resistance to the vaccine and it becomes less effective.
• B) The virus develops resistance to the vaccine.
• C) The virus can mutate into new strains.
• D) People change their habits each year and become susceptible to different strains of the virus.
• E) The common influenza virus can come from many species of animals including cats and dogs.

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Definitions:

Net Operating Income

Net operating income reflects the profit a company makes from its operations, exclusive of taxes and interest.

Variable Costs

are expenses that change in proportion to the activity of a business, such as raw material costs, which increase with the level of production.

Direct Labor

Factory labor costs that can be easily traced to individual units of product. Also called touch labor.

Contribution Margin

The amount by which sales revenue exceeds variable costs of production, indicating the contribution towards covering fixed costs.