Answer: Choice C
They should be blocked by pain resistance so the subjects are as similar as possible.
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Explanation:
The process of blocking in statistics is where we group up people in blocks, and each block is determined by a characteristic of some sort. In this case, we're grouping people up by pain resistance level. Those very resistant to pain will be in one group, while those who easily feel pain will be in another block, and so on. It might be effective to have a pain scale and sort people by that.
Blocking is done so that we eliminate unwanted variability. We are testing the effectiveness of the itching cream, so all we care about is if the itch reduces or not. We aren't worried about the levels of pain. However, it says that "Previous studies have shown the effects of treatment may vary based on a subject's pain resistance". So we group up the people by pain tolerance to help eliminate the variability of pain tolerance levels.
This is why choice C is the final answer.
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Extra info:
- Choice A is false because a person's name doesn't have anything to do with if the treatment works or not.
- Choice B is false because we weren't given any info to indicate it being true. It may be true, but we simply don't have enough info to confirm it.
- Choice C is false for similar reasons as choice B.
A line segment can have both line symmetry and rotational symmetry.
Answer: C )
Imagine there are 4 sits for fill for the debate team
we can fill the first sit in 35 different ways, second sit we only have 34 choices , third sit 33 and last sit 32 ways to possible fill it.
35·34·33·32=1,256,640 possible ways the team could be form
Answer:
Step-by-step explanation:
Hello, this is a geometric sequence so we are looking for a multiplicative factor.

So, the explicit formula is for n

Hope this helps.
Do not hesitate if you need further explanation.
Thank you