Astudy was done to examine the personal goals of elementary school children. a random sample of 500 students was selected from schools in the state of georgia. the students received a questionnaire regarding personal goals. they were asked what they would most like to do at school: get good grades, be popular, or be good at sports. the results are presented in the table, classified by the gender of the child. we wish to test the null hypothesis that gender and personal goal are independent. under the null hypothesis, the expected number of boys that would select "be good at sports" is