Read the passage that follows and them perform the requested mental simulation $..$ A firm managing a certain forestland is charged with maintaining a stable stock of mature trees, while doing some harvesting of trees each year for sale. Each year for the last $50$ years or so$,$ the firm has harvested a constant number of mature trees. In order to maintain the stock of mature trees at the specified target level, the firm follows a policy of re$-$planting a seedling for each mature tree it harvests in a given year. In this magically ideal forest preserve, no animals eat seedlings, and every seedling that is planted not only survives, but grows to maturity in exactly six years. Because the preserve has been operating in this manner for more than $50$ years, it is in "steady$-$state." This means that. an equal $($and constant$)$ number of trees is being harvested each year, an equal number of seedlings is being planted each year, and that same number of trees is also maturing each year. The stock of mature trees has therefore remained at a constant magnitude for $50$ years. Now, suppose that this year the firm decides to step up the harvesting of mature trees to a new, higher rate, and to then hold it constant at this rate for the foreseeable future. Mental simulation challenge: If the firm continues with its current replanting policy $($le$.,$ replant one seedling for each mature tree that it harvests$),$ and ideal conditions for seedlings continue to prevail in the preserve, what pattern, over time, will be traced by the magnitude of Mature Trees following the step$-$increase in the harvesting rate? Sketch your answer on a graph and explain your reasoning.