A school in New Zealand collected data about the employment status of the mother and father in two- parent families. The two-way table of column relative frequencies below shows the data.
Mother works full time
Mother works part time
Mother not working
Column total
Father works full time father works part time Father not working
0.17
0.14
0.13
0.23
0.14
0.07
0.60
0.71
0.80
1.00
1.00
1.00
Based on the data, which of the following statements must be true for the two-parent families at that
school?