You believe that the use of illegal substances is partially a function of shyness. You select a group of 600 adolescent boys from 9th to 12th grade from a representative sample of high schools in a Midwestern state. The average ave of the boys is 15.48 years. Participants reported how frequently they used illegal substances in the past month. Participants also completed the Cheek-Buss Shyness Scale. Does shyness predict illegal substance use? Question 17 (2 points) What is the INDEPENDENT variable in this problem? Question 17 options: adolescents Cheek-Buss illegal substance use shyness Question 18 (2 points) What is the DEPENDENT variable in this problem? Question 18 options: adolescents Midwestern high schools illegal substance use shyness Question 19 (2 points) What is the appropriate statistical test for this problem? Question 19 options: Pearsons correlation coefficient simple linear regression multiple correlation multiple regression