607. Why is this interval the best?
REST, MOTHER'S HEALTH 01
CHILD'S HEALTH 02
MOTHER'S AND CHILD'S HEALTH 03
CHILD'S EDUCATION 04
MOTHER'S HEALTH, CHILD'S EDUCATION 05
CHILD'S HEALTH AND EDUCATION 06
CUSTOMS, RELIGION 07
OTHER (SPECIFY) ____ 97
DOESN'T KNOW 98