| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.29 |
| Score | 0% | 66% |
Earth's history is divided into time periods, which of these is the longest time period?
age |
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epoch |
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eon |
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era |
The Earth is approximately 4.6 billion years old and its history is divided into time periods based on the events that took place and the forms of life that were dominant during those periods. The largest graduation of time is the eon and each eon is subdivided into eras, eras into periods, periods into epochs, and epochs into ages.
Which of these is matter than cannot be separated into different types of matter by ordinary chemical methods?
atom |
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molecule |
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compound |
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element |
An element is matter than cannot be separated into different types of matter by ordinary chemical methods.
What part of the food chain serves only as food for other organisms?
decomposers |
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producers |
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secondary consumers |
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primary consumers |
Producers (autotrophs) serve as a food source for other organisms. Typical producers are plants that can make their own food through photosynthesis and certain bacteria that are capable of converting inorganic substances into food through chemosynthesis
Leafy vegetables, beans, potatoes, fruits, and whole grains are good sources of:
unsaturated fat |
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fiber |
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protein |
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saturated fat |
Fiber provides bulk to help the large intestine carry away waste. Good sources of fiber are leafy vegetables, beans, potatoes, fruits, and whole grains.
Which of the following is the formula for work?
\(W = {{F}\over{d}}\) |
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\(W = {\vec{F} \over \vec{d} }\) |
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\(W = {F}{d}\) |
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\(W = \vec{F}\vec{d}\) |
Work is performed on an object when an applied force causes displacement along the same vector. Measured in joules (J) or newton-meter (Nm), work is calculated by multiplying force times displacement: \(W = \vec{F}\vec{d}\)