Well let's see how many numbers can be divisible by 6 or 8, add them up, and then put it into a fraction.
6: 6, 12, 18, 24, 30, 36.
6: 8, 16, 24, 32, 40.
Total:
6, 8, 12, 16, 18, 24, 30, 32, 36, 40.
There are 10/40 positive numbers that can be divided by 6 or 8.
Simplified, 1/4.
They are can be except for wind weathering i believe. That is caused by the wind.
Ocean trenches are created by the moving apart of tectonic plates, volcanoes are pushed to erupt by the movement of tectonic plates and earthquakes are cause by the movement also.