Carmen conducted an experiment to determine if listening to different types of music would affect a person's pulse. her hypothesis was that pulse rate would change with different types of music. each person listened to seven different selections of music for 30 seconds each. each person's pulse was taken before the music and then after each 30-second interval of music. the pulses were taken again after the music selections were completed. based on her experiment, carmen concluded that a person's pulse rate changed when the person listened to different types of music. which component is missing from carmen's experiment?

The answer is "The experiment is missing a control group."

Control group, the standard to which examinations are made in an experiment. Numerous experiments are intended to incorporate a control gathering and at least one trial gatherings; truth be told, a few researchers hold the term analyze for contemplate outlines that incorporate a control gathering. In a perfect world, the control gathering and the exploratory gatherings are indistinguishable inside and out with the exception of that the test bunches are subjected to medicines or interventions  accepted to affect the result of intrigue while the control amass isn't.  

the density would be a smaller number.

answer; 55-85;