With a world population in 2003 of 6.314 billion and a projected population growth rate of 1.1% instead (which is the United Nations' projection for the period 2003 to 2015).

Compute the doubling time.
State the year in which the world's population would be 12.628 billion.
Suppose a country's population grows at the rate of 2% per year and its output grows at the rate of 3% per year. Calculate its rate of growth of per capita output.
If instead its population grows at 3% per year and its output grows at 2% per year, calculate its rate of growth of per capita output.