piece of square wood, after cutting it into three pieces, the surface area increases by 80 square centimeters, and the length is 3 meters. The weight of wood per cubic decimeter is 450 grams. How many kilograms does this piece of wood weigh?
一段方木条，把它截成三段后，表面积增加80平方厘米，长3米．每立方分米木重450克，这段木条重多少千克？
<result>2.7</result>