They are heavier because they absorbed the water.
they are caused by mutation. the best example of it are human blood groups.
I believe the answer is D) reactivity. Hope this helps. (ﾉ◕ヮ◕)ﾉ*:･ﾟ✧
This is the chronicle of evolution over millions of years of geologic time engraved in the order which fossils appear in rock strata.
D identity disorder is characterized by the presence of two or more distinct personality identities. Each may have a unique name, personal history, and characteristics.
