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When a comet collides with earth, it adds material to our planet and causes great damage. therefore, a collision like this is a a. destructive force b. constructive force c. geologic process and event d. constructive and destructive force

12. calculate the hydroxide ion concentration of a solution with ph = 3.25. show all calculations leading to an answer

Which of the following is a physical property flammability heat of combustion solubility and toxicity