[Q]: David was studying for his chemistry exam. To understand the elements of the periodic table better he categorized them into three groups, cat A, cat B, and cat C. In cat A he placed all the elements with atomic numbers lower than 83. In cat B he put the elements with atomic numbers from 83 to 94. Finally, in cat C he placed the elements with atomic numbers over 94. He found it easier to see their differences after he categorized them. Which category would have shorter half-lives, cat B or cat C?
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[A]: cat C

[Q]: Bob works as a scientist for a large fishing company in Norway. Norway's government has strict regulations on fishing to protect its fish stock. Part of Bob's job is to provide the government with fish mortality data. Today, he has two samples of fish to investigate, sample A and sample B. Bob concluded sample A had natural mortality, but sample B had fishing mortality. For which sample disease would not be a cause of death, sample A or sample B?
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[A]: sample B

[Q]: A doctor tested two people for HIV. Tom had the virus in his blood, while Nick didn't have HIV, he was healthy. Tom has apparently had the virus for 20 years. Which person didn't have the ability of the immune system to defend the body decreasing?
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[A]: Nick

[Q]: Anna is going grocery shopping today. She gets to the meat section and decides to buy some ground beef. While looking at the cases she notices 2 brands of meat, Brand A and brand B. Bother were packaged the same day but package B's meat is noticeably more brown in color. Given package A was treated with carbon monoxide, which will it have more of compared to package B, oxymyglobin or carboxymyglobin?
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[A]:
carboxymyglobin