Ksp = [Ba⁺²][SO₄⁻²]
[Ba⁺²] = [SO₄⁻²] for barium sulfate
Thus,
Ksp = (1 x 10⁻⁵)²
Ksp = 1 x 10⁻¹⁰
Answer:
The answer is 0.83 seconds.
Explanation:
The formula of free fall is following:

Where g=9.8 m/s^2 and t=2 seconds, the rock takes:

19.6 meters. This is the half distance of the cliff. The whole distance is 39.2 meters. So it takes:

2.83 second to fall down completely. The rock takes the second half of the cliff in 0.83 seconds
6 months with no sunrise and the other 6 without a sunset, at some places on Earth, are the result of the orientation of Earth's axis.
C) alternately increase and decrease