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Kevin and randy muise have a jar containing 78 coins, all of which are either quarters or nickels. the total value of the coins in the jar is $13.90. how many of each type of coin do they have?

Which function is increasing? o a. f(x)=(1/15)* o b. f(x)= (0.5)* o c. f(x)=(1/5)* o d. f(x) = 5*

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?