While I am in air, I am not in oxygen.
I am also in water, but not in hydrogen.
I am necessary in all animals, but you won't find me in the zoo.
Look in all brains and you'll find me there too.
What am I?
Dave is put in a cell with a dirt floor and only one window.
The window is too high for him to reach.
The only thing in the cell is a shovel.
He won't be able to get any food or water and only has two days to escape or he'll die.
Dave can't dig a tunnel because it will take him much longer than two days to do it.
How will Dave escape from the cell?
Dave has to use the shovel to create a pile of dirt under the window so he can climb up onto it and escape from the cell.
