There are two factors that are considered very important: ____ levels and ____ levels. The average number of people ____ in a specific place and time, and who ____ mint theexisting population is called ____. The number of people, who ____ in a specific place and time,and the existing population ____ is called ____.

Birth and Mortality

由
嵌入

排行榜

視覺風格

選項

切換範本

恢復自動保存: ?