i need know :)

Round your final answer to the nearest year. Research indicates that a country has 6.2 x 101m? of arable land available. The population of the country in 1957 required 100 m to sustain it, and the population of 1986 required 5 x 100m. If the required area grows at a constant percentage rate, in what year will the population reach the maximum sustainable size? This occurs in the year