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How many atoms are in 1.4 mil of phosphorus trifluoride (pf3)

Which of the following methods uses the decay of atomic particles in an object to find its exact age? a. fossil dating b. geologic dating c. radioactive dating d. relative dating

Maria wants to determine which type of disinfectant kills the most bacteria. which of the following is the best way for maria to determine this? a. ask ten different companies that make disinfectants which type is best. b. put the same amount and species of bacteria on ten identical plates, and add ten different kinds of disinfectant to each plate. c. interview ten different people to determine which type of disinfectant they prefer. d. put the same amount and species of bacteria on ten identical plates, and add a different disinfectant to each plate.