It would mean that you could not know the precise volume of the sand. Only the volume of the sand plus the water that was making it damp.
In the experiments listed, the effects are easy to deduce by understanding that the water in the sand adds volume to the 'sample' being measured.
So in the case of calculating air space you would calculate <em>less</em> air space.
5.16 meters!!!!!!!!!!!!!!!!!!!!
Explanation:
Charges,

The distance between charges, r = 10 cm = 0.1 m
We need to find the magnitude and direction of the electric force. It is given by :

So, the required force between charges is 36 N and it is towards positive charge i.e. +8 μC.
I personally would live on Mars cuz that is red cuz