The answer will depend on how long the hole is. The hole has 3 dimensions that determine its volume. You have provided measurements of only two dimensions.
24 feet
A hole does not have dirt!
There is no dirt in a hole that is 3 feet deep and six inches in diameter.
Without knowing the width of the shovel, it's not possible to calculate the volume of the hole. But whatever its volume is, there's no dirt at all in the hole.
None. Once you dig it, it is out of the hole, not in it.
There is no dirt in a hole because a hole is defined by the absence of material, in this case dirt. If you were to fill the hole with dirt, it would require 24 cubic feet of dirt to completely fill it.
There is NO dirt, it is a hole! If you want to fill it with dirt, that is 4x6x12=288 cubic feet, weighing about 28,800 pounds
The question cannot be answered in a sensible way. The size of the hole is given in only two dimensions - in all likelihood, that means the area that the hole covers but not how deep it is. The amount of dirt required to fill the hole will depend on the depth of the hole as well.
None because it's a hole but 6 cubic yards of dirt will fill it up.
None. If there was, it would no longer be a hole!
None, if it is a hole.
Theoretically, none. The amount of dirt excavated to create such a hole would be 1 cubic metre. However, excavated dirt (depending on the nature of the dirt) can increase in mass by up to a third the original size. That is why when you dig a big hole then fill it in (getting all the dirt back) the hole is raised on top not flat.
If it's a hole, there would be no dirt in it, right?
Yes as it would be an area that can fill with dirt or "grease" as it be.
24 feet
10-1/2 cubic yards
10*13*3 = 390 cubic inches.