Please answer this: In his chemistry lab David is learning about acids. He took three solutions to identify them correctly, sample A, sample B, and sample C. Sample A is a strong acid; sample B is a weak acid; and sample C is not an acid. David needs to identify the content of each sample by learning about their attributes. Which sample would have pH lower than seven, sample A or sample C?
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Answer: sample A

Please answer this: Two friends, John and Abe, worked at the same warehouse. John was exposed to very strong light all the time, while Abe worked in a more normal environment. John started experiencing health problems after a while. Which worker experienced weaker effects on alertness and mood, John or Abe?
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Answer: Abe

Please answer this: David got five exercise tips from his personal trainer, tip A, tip B, tip C, tip D, and tip E. Tip A involves weight lifting, but tip B does not involve weight lifting. Tip C involves running, but tip D does not involve running. Finally, tip E does not involve any exercise at all. David has to find out which tips are most useful for him. Would tip D make the cardiac muscle more efficient or not more efficient than tip C?
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Answer:
not more efficient