When do we say that a star is born?
A. when the interstellar cloud collapses
B. when the interstellar matter achieves the Jeans instability
C. when the star leaves the main sequence
D. when fusion of hydrogen atoms into helium atoms starts
Answer: D
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When lying down, the gauge pressure of the blood at a patient's heart is 13.3 kPa. If the patient suddenly stands up and her body doesn't compensate quickly enough for the pressure changes, what would be the pressure at her head, 55.0 cm above her heart? The density of blood is 1 060 kg/m3
a. 7.59E+3 Pa b. 5.71E+3 Pa c. 1.90E+4 Pa d. 5.85E+5 Pa
Wave interference occurs for waves of
A) sound. B) light. C) water. D) all of the above E) none of the above
A fault in which the footwall has moved down relative to the hanging wall is called a
A) normal fault. B) reverse fault. C) transform fault. D) horizontal fault.
Which gases are added to Earth's atmosphere by volcanic eruptions?
A. carbon dioxide, ozone, and methane B. carbon dioxide, water vapor, and nitrogen C. nitrogen, oxygen, and ammonia D. ammonia, methane, and oxygen