The answer is C.15, USSR broke into 15 republics including Russia itself.
Explanation:
Italian astronomer Galileo Galilei discovered four of Jupiter's moons , in year 1610 . Now these are known as Io, Europa, Ganymede, and Callisto. Io is innermost of these four moons and one of the most volcanically active planetary object still discovered. These moons are very much different from any other planetary body in every respect. The Voyager spacecraft pictures show that the surface of the moon io is completely covered by volcanoes and lavas rather being covered by pitts and craters. this gives the surface a very young look. The main cause of the intense volcanic activity found out here is the strong gravitational force created at the center of the moon from the Jupiter and Europa. Due to the synchronous rotation with Jupiter, solid materials at the surface of io bulges up just like the tidal motions of the oceanic water in the case of Earth. This repeated bulging causes the materials to get hitted up in a manner similar to repeatedly stretching and smashing a clay ball or rubber band. This enormous amount of heat generated in the process melts rock materials at depth and results in widespread volcanisms.
Hypotheses to explain different levels of volcanism:
a) This is very much evident that the volcanic activity is largely driven by the gravitational forces of the Jupiter. If the moons are at different distances from the large planet then the gravitational pull will be also varying for the moons and this will cause differential amount and types of volcanic activity at the moon's surface.
b) In case of io, the moon is largely made up of iron and iron sulphide core and a silicate outer surface. This silicate outer surface of the moon melts down to create the widespread volcanic activity. In case of Europa the outer surface is made up of vast quantity of water and ice. So there is lesser chance of volcanic activity in this moon. So the volcanic activity is greatly controlled by the lithological composition of the moon.
c) There is a vast amount of sulphur present at the interior of io which gets degassed and comes to the surface to create the fierce nature of the volcanisms. These gases are essential for a violent volcanism, and controls the nature and level of volcanism.
The geologic history of the Earth is broken up into hierarchical chunks of time. From largest to smallest, this hierarchy includes eons<span>, eras, periods, epochs, and ages.
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Bubonic plague effected on European feudalism as it hastened feudalism's decline due to the system's reliance on peasant labor.
Answer: Option A
<u>Explanation:
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Bubonic Plague was an epidemic disease which had spread in Europe in 14th century and resulted in the death of 30-60% of European population. This deadly disease has also resulted in the decline of Feudalism.
The system of feudalism largely dependent of the peasants or labourers which were known as serfs who were employed by the knights and worked under the barons( who worked for the kings).
The Black death or the plague had affected the peasants the most hence breaking the system as the now there was great shortage of labour.
Physical processes are the natural forces that change earths features.
