At the start of the 27th century, the population of Zosania was approximately 40 million. Early-century prosperity saw the population nearly double in the first three decades, but the growth slowed in the 30s and 40s and then leveled off completely during the war years in the 50s. A postwar boom saw another rapid population increase, but that turned around in a major decline resulting from the great famine of the 70s. A slow end-of-century rebound resulted in an increase of the population to approximately 90 million at century’s end. Let P represent the population in millions and t represent time in years since the start of the century. Make sketches of the graphs of P and P' as functions of t for Zosania’s population during the century.