Answer:
The existance of dark energy was suggested to help explain measurements, using Type Ia supernovae as distance indicators, that the expansion of the universe is speeding up and its acceleration requires a source of energy. Scientists suggested that It may be a new form of energy for which there is not yet a theoretical explanation. quantum mechanics predict that it may be the vacuum energy associated with "empty" space itself.
Mass of oxygen stays the same.
Kevin is a unit used to measure temperature
The magnitude of the work done to push the object is 90,000 J
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When is Work done on a body ?</h3>
Work is done on a body when the direction of the force applied is parallel to the direction of the displacement of the body.
The following parameters are given;
First convert the distance in kilometer to meter by multiplying it by 1000
S = 1.2 x 1000 = 1200 m
From the definition of work,
W = F x S
Substitute the parameters into the formula
W = 75 x 1200
W = 90,000 J
Therefore, the magnitude of the work done to push the object is 90,000 J
Learn more about Work here: brainly.com/question/25573309
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