Answer the following question given this paragraph: Flaps of tissue called valves separate the heart's chambers. Valves keep blood flowing in just one direction through the heart. For example, a valve at the bottom of the right atrium opens to let blood flow from the right atrium to the right ventricle. Then the valve closes so the blood can't flow back into the right atrium. Q: What is the largest artery in the body called? Choices: - ventricular - carotid - radial - aorta A:
aorta
(Question)
Answer the following question given this paragraph: Most of the organisms that once lived on Earth are now extinct. Earth's environment has changed many times. Many organisms could not adapt to the changes. They died out. The organisms that did survive passed traits on to their offspring. The changes added up, eventually producing the species we see today. Q: Species of organisms that have permanently died out can also be called what? Choices: - succinct - inherited - occuring - extinct A:
(Answer)
extinct
Ques: Answer the following question given this paragraph: Covalent bonds are responsible for many of the properties of covalent compounds. Covalent compounds have relatively low boiling points, cannot conduct electricity, and may not dissolve in water. Q: What is responsible for many properties of covalent compounds, which have relatively low boiling points, cannot conduct electricity, and may not dissolve in water? Choices: - ionic charge - accretion bonds - atomic weight - covalent bonds A:
Ans: covalent bonds
(Q).
Answer the following question given this paragraph: The thermosphere is the layer above the mesosphere. Temperature increases with altitude in this layer. The northern and southern lights occur here. Q: In which sphere of the atmosphere do the northern and southern lights occur? Choices: - lithosphere - stratosphere - ionosphere - thermosphere A:
(A).
thermosphere
Ques:Answer the following question given this paragraph: Geysers erupt because the water is trapped. The water becomes superheated until finally the pressure builds enough for it to break the seal. Q: Geysers erupt because what boiling hot substance is trapped beneath their surface? Choices: - gas - lava - oil - water A:

Ans:water
Question: Answer the following question given this paragraph: Q: Ciliary muscles control the shape of the lens, which bends light and focuses it on what? Choices: - the pupil - the vitreous fluid - the cornea - the retina A:
Answer:
the retina