Why is the average atomic mass used when calculating grams of a substance? A. The number of isotopes in the sample is constantly changing. B. The average atomic mass is known to more significant figures, O C. The elements in the substance are mixtures of their isotopes. D. The exact weights of the isotopes are not known.​

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.

When the water vapor cools it condenses select a number that represents his process on the

Asuspension of yeast cells is being grown under anaerobic conditions such that glucose is degraded to ethanol and carbon dioxide. if one wishes to follow this process by monitoring the release of 14co2, at which positions in the glucose molecule would the 14c label need to be incorporated?