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Answer: a.The mirrors and eyepiece of a large telescope are spring-loaded to allow them to return quickly to a known position. </h2>
Explanation:
Adaptive optics is a method used in several astronomical observatories to counteract in real time the effects of the Earth's atmosphere on the formation of astronomical images.
This is done through the insertion into the optical path of the telescope of sophisticated deformable mirrors supported by a set of computationally controlled actuators. Thus obtaining clear images despite the effects of atmospheric turbulence that cause the unwanted distortion.
It should be noted that with this technique it is also necessary to have a moderately bright reference star that is very close to the object to be observed and studied. However, it is not always possible to find such stars, so a powerful laser beam is used to point towards the Earth's upper atmosphere and create artificial stars.
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Time = (displacement) / (magnitude of average velocity) .
The density of an object can be calculated using the formula Density = Mass/Volume. In this case however we are searching for the volume and must rearrange the formula so that we are solving for the volume. If you multiply both sides by volume and then divide both sides by mass you end up with the equation Volume = Mass/Density.
Volume = 1500g/1.5g/cm^3
Volume = 1000 cm^3