Robert is nine years old and Joanna is seven. They live at Mount Ebenezer. Their father has a big property. In Australia they call a farm a property. Robert and Joana like school very much. At school they can talk to their friends, but Robert and Joanna can not see their friends. They live 100,perhaps 300,miles away and like Robert and Joanna, they all go to school by radio. Mount Ebenezer is in the centre of Australia. Not many people in "The Centre", there are no schools with desks and blackboards and no teachers in "The Centre".  School is a room at home with a two-way radio. When all students answer, lessons begin. Think of your teacher 300 miles away! In order to send their children to school, parents in "The Centre" of Australia must have   _  .
a property a car a school room at home a special radio