The Gross Domestic Product per capita in China (a middle income country) was last recorded at about 18,000 US dollars in 2021, when adjusted by purchasing power parity (PPP). How large will the per capita GDP for China be if it grows at an annual rate of 2% for 10 years? 2% for 30 years? 4% for 10 years? 4% for 30 years? Explain why the difference between 2% and 4% growth matters?.