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Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

How do limiting factors most affect population size? ostop population growthrestrict population growthincrease population sizeresult in positive impactso

Which of the following characteristics are true of enzymes? check all that apply. a.)the structure of an enzyme can change if conditions change. b.)a single enzyme can normally catalyze a wide variety of reactions under many conditions. c.)enzymes are found only in nonliving systems. d.)enzymes allow living things to regulate body conditions through feedback mechanisms. e.)enzymes bind to specific substrates in specific ways. f.)enzymes increase the rate of reaction. g.)when shown in energy-reaction diagrams, enzymes represent the higher activation energy.