参考答案和解析
正确答案：
E
解析：
Since the sum of the sectors of a circle graph must add up to 100%, x% + 20% + 28% + 12% + 24% = 100%, x= 16. Since 16% + 24% = 40%, then 0.40 × 2500 or 1000 students named either swimming or biking as their favorite sports activity.
