Your heart's mitral valve does an awfully big job. Letting blood from the left atrium of the heart into the left ventricle without losing a drop is one of
... [Show More] the toughest tasks in the circulatory system. In fact, if the system was suddenly opened at that point, the force of the valve closing would send blood five feet in the air.
In this passage, the author's purpose is to
A. describe the circulatory system
B. convince readers of the stress on the mitral valve
C. inform readers of defects in the mitral valve
D. minimize the importance of the mitral valve
B. convince readers of the stress on the mitral valve
Riding the mail plane is a low-budget way to visit America's largest national park - Wrangell St. Elias - 13 million acres of scenic beauty. Copper first drew prospectors to this part of Alaska. From 1991 to 1938, the Kennicott mine produced 200 million tons of it. Now a mecca for tourists, the town of Kennicott was abadones to the ghosts when the copper ran out.
According to the passage, which of the following illustrates the correct sequence of events?
A. copper drew prospectors, copper ran out, town abandoned, tourist attraction
B. copper crew prospectors, tourist attraction, copper ran out, town abandoned
C. copper drew prospectors, copper ran out, tourist attraction, town abandoned
D. copper drew prospectors, tourist attraction, town abandoned, copper ran out
A. copper drew prospectors, copper ran out, town abandoned, tourist attraction
Physicists seek out those features of nature that are simple and universal. The secret of their success is not so much a matter of finding the answers as it is asking the right questions. The trick is keeping the questions simple and sticking to universal phenomena. Simple questions can be answered unambiguously by careful observation of repeated experiments and by logical thinking.
Which of the following questions is most clearly an example of the kind discussed in the paragraph.
C. how fast do stones of a particular size fall?
An allergy is a hypersensitivity to substances that are essentially harmless. For as yet poorly understood reasons, the immune system malfunctions and marshals up an army of antibodies to fight these substances. For many allergies, this malfunction causes a large amount of histamine to flood into the bloodstream. It is the overabundance of histamine that causes allergic symptoms such as headaches, rashes, and sneezing.
The passage states all of the following about allergies EXCEPT
B. an allergic reaction is the result of a false alarm in the body's immune system
A period of time is usually measured by comparing it with another period of time. For example, a year on Mercury is equal to 88 Earth days. A year on Uranus is approximately 348 Mercury years.
According to the passage, the way time is usually measures shows that time is
B. relative
From Texas to Southern CA, low-water maintenance landscaping and the popularity of desert themes have made cactus very valuable. Considering the fact that cactus have extremely slow growth and reproduction rates, rustlers anticipate significant profits of this shallow rooted succulent. Removing cactus from state-owned land, however, is a felony, and if state lines are crossed, the 1900 Lacey Act makes this same crime a federal offense.
From the passage, determine the sequence of events
B. cactus popularity, transport of stolen cactus, cactus theft
Weather radar is a great help to pilots in detecting thunderstorms. However, pilots must be aware that radar does not reliably detect hail....
According to the paragraph, weather radar does not reliably detect hail because of
C. faulty pulse transmission by radar
According to Mark Twain, October is a particularly dangerous month to speculate in stocks....
What was Mark Twain's point?
-certain times of the year better than others for buying stocks.
- october is an especially bad month for speculating stocks.
-speculating in stocks is not a safe investment for your money
-it's always a good time to make a sound investment in stocks.
Speculating in stocks is not a safe investment for your money
an analysis of the mandatory oil quota program shows that separate quotas were establish for crude oil and for petroleum products.the passage implies which of the following about the oil quota program
The quota for residual fuel oil products was the same as for crude oil products
physical sound energy is transmitted through the external ear and the middle ear to the inner ear where it creates pressure waves. where is the organ of corti located
C. inner ear
the woman's flying training detachment was the brainchild of Jacqueline Cochran. the famous flyer. because of the overwhelming demand for qualified men to fly in combat during world war 2. she was able to persuade the army to train women pilots to ferry military aircraft from manufactures to embarkation points for later shipment overseas.
The author implies that the primary motivation for establishing a training program for women pilots during world war 2 was the:
- army's wish to utilize women's ability
- unavailability of qualified men pilots
-fame of flyer Jacqueline cochran
- existence of the women's flying training detachment
Unavailability of qualified male piolts
the lens of the eyes focus light rays as the enter the eye. muscules around the lens react to light and change the shape of the lens by expanding or contacting.certain diseases or injury to the lens of the eye can result in blurry vision.according to the paragraph the lens of the eye is used to
focus light [Show Less]