Alfred Kroeber did explain the theory of environmental determinism first so that means the statement is true.
I need the choices to be able to help you...
"The Silurian is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago, to the beginning of the Devonian Period, 419.2 Mya.<span> <span>Wikipedia."
https://www.google.com/search?q=He+Silurian+period+occurred&rlz=1C1RUCY_enUS760US760&oq=He+Silurian+...
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#10 is incorrect, the correct answer is Korea.
#11 is incorrect, the correct answer is Japan.
#13 is incorrect, the correct answer is Communist.
#14 is incorrect, the correct answer is Collective Farms.
#15 is incorrect, the correct answer is Ganges River.
As far as I know, all other answers are correct.
Feel free to ask for explainations.