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Natural resources are any materials that humans obtain from the earth to meet our wants and needs.

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic

Which of the following best describes the purpose of the parathyroid hormone? a. it decreases the blood calcium level and decreases blood phosphorus level. b. it decreases the blood calcium level and increases the blood phosphorus level. c. it increases the blood calcium level and increases blood phosphorus level. d. it increases the blood calcium level and decreases blood phosphorus level.