How many cubic miles of water on earth is stored as groundwater? how many cubic miles of water on earth is stored in rivers and lakes? how many cubic miles of water on earth is stored in glaciers and icecaps?

The estimated total amount of water on Earth is 333 million cubic miles. Of the fresh water that accounts for the 2.5% which is equal to 8.325 million cubic miles, 30.1 % is groundwater, 1.2% is stored in rivers and lakes, and 68.7% is found in glaciers and icecaps. These translate to the amount of 2.5 million cubic miles, 0.0999 million miles, and 5.72 million miles, respectively. 

that is wrong, its not thymus.