Question: Write out all the figures in Example numerically; write down the relevant relations; and confirm the statements made.
Example: Now try some comparisons for a number that may have some more immediate interest than the volume of the Earth. The annual federal budget is on the order of four trillion dollars ($4 × 1012). What is a trillion dollars? Try breaking the number into more manageable units, say 100 million dollars. It takes ten thousand sets of 100 million to make one trillion. One hundred million is still hard to imagine, but its scale is more tangible. For example, a medium-sized liberal arts college has a yearly budget on this order, or quite a nice hospital might be built for $100 million. Even so, forty thousand hospitals a year is hard to imagine. But when you discover that 4 trillion dollars could build more than 100 new, fully equipped, 40-bed hospitals every day for a year, you begin to get a sense of what $4 trillion means.