The answer is that exact locations within either cannot be determined at any given moment in time.
An electron cloud be compared with a spinning airplane propeller in the manner that in both exact location within either cannot be determined at any given moment in time.
In both electron cloud as well as spinning airplane propeller, there is a probability of finding either but exact location can not be determined.
A cloud that forms on the ground is called fog. Some clouds you see in the sky might be from airplanes. These are called contrails. High level cirrus clouds may travel at speeds up to 100 mph.
It is greater than the total mass
I’m pretty sure it’s A) upper right!