题目

You change the channels for the fourth time and realize that once again there’s nothing on television that gets your attention. Not a problem! Throw on some running shoes and comfortable clothes and go for a run. One of the coolest things about the sport of running is that you don’t need expensive equipment(装备). All you need is a good pair of running shoes and a safe environment. But just because you don’t need much equipment don’t be fooled into thinking the sport of running is easy. No one wakes up and decides to run a marathon without training. Running makes your heart李大伯承包了一片荒山，在山上种植了一部分优质油桃，今年已进入第三年收获期．今年收获油桃6 912千克，已知李大伯第一年收获的油桃重量为4 800千克．试求去年和今年两年油桃产量的年平均增长率，照此增长率，预计明年油桃的产量为多少千克？