Answer:
4.modifying a building to achieve an entirely new purpose
The KVA rating of the step down transformer at the given power factor would be 62.5 kVA.
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What is power factor of a transformer?</h3>
Power factor (PF) is the ratio of working power, measured in kilowatts (kW), to apparent power, measured in kilovolt amperes (kVA).
PF = working power / apparent power
PF = kW/kVA
kVA = kW/PF
kVA = 50 kW/0.8
kVA = 62.5 kVA
Thus, the KVA rating of the step down transformer at the given power factor would be 62.5 kVA.
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Answer:The Wright brothers invented and flew the first airplane in 1903, recognized as "the first sustained and controlled heavier-than-air powered flight". ... Airplanes had a presence in all the major battles of World War II. The first jet aircraft was the German Heinkel He 178 in 1939.
Explanation:
Answer:

Explanation:
= Energy for defect formation = 1.86 eV
T = Temperature = 
k = Boltzmann constant = 
The fraction of lattice sites that are Schottky defects is given by

The required ratio is
.