Force is determined by multiplying mass and gravity (F= mg). To determine the answer, the mass of the elephant (5600 kg) is multiplied with the gravity (9.8 m/s²). The answer is 5800 N. This is the upward gravitational force that the elephant exerts on the earth.
Single replacement would be represented by a single element being replaced.
This is shown in answer choice B
Where the positions of A and B are swapped
Distance = 2AU / tan1.0
If you mean 1.0 is in degrees, then Distance = 114.58 AU
