| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.96 |
| Score | 0% | 59% |
Earth's history is divided into time periods, which of these is the longest time period?
age |
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era |
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eon |
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epoch |
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.
Elements in the Periodic Table of the Elements are ordered by which of the following?
atomic number |
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atomic mass |
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atomic weight |
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number of electron shells |
The Periodic Table of the Elements categorizes elements primarily by the number of protons in their nucleus (atomic number) and secondarily by the characteristics they exhibit.
Neurons are part of the __________ nervous system.
peripheral |
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autonomic |
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somatic |
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central |
The nervous system consists of the brain and spinal cord (central nervous system) and the peripheral nervous system which is the network of nerve cells (neurons) that collect and distribute signals from the central nervous system throughout the body.
__________ and __________ pair to strengthen bones.
vitamin D, magnesium |
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calcium, vitamin A |
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iron, calcium |
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vitamin D, calcium |
Vitamin D helps calcium strengthen bones while also aiding muscle, nerve, and immune system function.
Which of the following is the formula for work?
\(W = {F}{d}\) |
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\(W = {\vec{F} \over \vec{d} }\) |
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\(W = {{F}\over{d}}\) |
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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: \(W = \vec{F}\vec{d}\)