Well in the population from births and death it’s often combined and referred as natural increase or change, populations grow or shrink depending on if they gain people faster than lose them.
If in an eight-cell embryo of an organism, the cells of the upper tier are aligned over the cells of the lower tier at a slight angle, it is likely that the organism is a vertebrate.
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Hi.
After a quick search, I'm pretty positive you're supposed to use the wafting technique.<em>
</em><em />Hope this helps.<em>
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