An article from October 3, 2007 in The Washington Post about how paper and plastic bags impact the environment, stated that:

Worldwide, an estimated 4 billion plastic bags end up as litter each year. Tied end to end, the bags could circle the Earth 63 times.

(a) Are the numbers 4 billion plastic bags and circle the Earth 63 times consistent?

(b) Use an estimate of the population of the United States and some common sense to estimate how many plastic bags are used in the United States each year. Use your answer to show that the 4 billion plastic bag claim is too small by several orders of magnitude.