Which of the following is an example of a trade barrier?

tariff

Which of the following drives the free market economy?

the needs and wants of the people

the needs and wants of the people

the supply of goods in the market

the supply of goods in the market

the number of consumers in the market

the number of consumers in the market

the gross domestic product

the needs and wants of the people

Which term describes the choices that people must make to meet their wants and needs?

supply

supply

demand

demand

opportunity cost

opportunity cost

producers

producers

opportunity cost

Use the drop-down menu to complete the sentence.

One disadvantage to using a primary source, such as a letter or diary is _______

A. the source could be lost
B. the source could contain bias
C. the source may not be well-written
D. the source could be inaccurate.

B. the source could contain bias

What function do the alveoli perform?

carry oxygenated blood away from the heart
carry oxygenated blood away from the heart

exchange oxygen in the blood for carbon dioxide in the air
exchange oxygen in the blood for carbon dioxide in the air

exchange oxygen in the air for carbon dioxide in the blood
exchange oxygen in the air for carbon dioxide in the blood

hold receptors for the sense of smell

exchange oxygen in the air for carbon dioxide in the blood

Which organ of the respiratory system is located inside the lungs?

trachea
trachea

larynx
larynx

nasopharynx
nasopharynx

bronchioles

bronchioles

A patient has low blood oxygen levels, although the patient's blood is circulating properly. Which is most likely functioning improperly?

the pulmonary vein
the pulmonary vein

the aorta
the aorta

the capillaries
the capillaries

the alveoli

the alveoli

What is the function of the vena cava?

It carries oxygenated blood from the heart to the body.
It carries oxygenated blood from the heart to the body.

It carries deoxygenated blood from the body to the heart.
It carries deoxygenated blood from the body to the heart.

It carries oxygenated blood from the lungs to the heart.
It carries oxygenated blood from the lungs to the heart.

It carries deoxygenated blood from the heart to the lungs.

It carries deoxygenated blood from the body to the heart.