Answer:
I'm not sure it is c I'm sure it is d
Quantum theory is the theoretical basis of modern physics that explains the nature and behavior of matter and energy on the atomic and subatomic level. The nature and behavior of matter and energy at that level is sometimes referred to as quantum physics and quantum mechanics.
It is called the reaction force of a bird flying.
Answer
Factors Affecting Acceleration Due to Gravity
(1) Position on the planetary surface, it is higher at the axis (poles),
(2) Mass of the planet, higher with planets of larger masses
(3) Distance between object and the centre of planet, the larger the distance, the smaller the acceleration due to gravity.
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