应用成本比例计算期末存货

applying cost ratio to ending inventory

使用期间应保持良好生活习惯，确保达到至佳效果。

В период применения необходимо придерживаться хороших привычек (избегать вредных привычек), чтобы обеспечить наилучший эффект.

中国首先发明指南针。战国时期，中国已经用磁石制成了指南的仪器，古人称它为“司南”。北宋时，又发明了用天然磁石摩擦钢针制成的罗盘针，即真正的指南针，并应用于航海。13世纪指南针传到欧洲。

The compass was invented in China. As early as in the Warring States Period (450 B. C. -221 B. C. ), a magnet was used as a device that pointed to magnetic north, and this device was named “Si Nan” by the ancient Chinese. In the Northern Song Dynasty (960 A. D. -1127 A. D. ), another device was invented with a magnetic iron needle that pointed to magnetic north, and this device was later used in navigation. The compass was introduced to Europe in the 13th century.