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If the root word engage means “to connect with something,” what does the word disengage mean in the following sentence? he disengaged the gears by stepping on the clutch pedal. a.added more engine powerb. activated a connection to the pedalc. stalled the engined. released a connection to the pedal

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.

Significant figures are digits read directly from the measuring instrument plus one more digit, which is __ by the observer.