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What is the length of bc ? enter your answer in the box.bc =

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?

The probability that you roll a two on a six-sided die is 1 6 16 . if you roll the die 60 times, how many twos can you expect to roll