Divide 40 students in a class of the fourth grade into several groups on average. How many ways are there to make the number of students in each group even? (Please write down the possible number of people in each group.)
把四年级一个班40名学生平均分成若干小组，要使每组中的人数都是偶数，共有多少种分法？(请把每组可能的人数写出来．)
<result>5</result>