The following text is for questions 19 to 21.

One Sunday afternoon, Mawar and Mr. Sholeh went talking about. Mawar's plan of having a small library for children in their neighborhood.
"Dad, many children in our neighborhood are crazy about online games. Their literacy activities are very low," Mawar said.
"Yes, ifs very pitiful. You know, literacy is very important. They can broaden their knowledge by reading," Mr. Sholeh said. 
"You're right. Actually I want to open a library for them," replied Mawar.
"Good idea. Where are you going to make the library?" asked Mr. Sholeh.
"I think the park is a good choice. Children can read books under trees, on benches or in gazebos. It will be more interesting," explained Mawar.
"O.K. Then, where will you put the books?" asked Mr. Sholeh.
"I can put them in the baggage of our car, Dad. It is like a mobile library," said Mawar.
"That's great! l will help you find donation for books. I will discuss it with the chief of residence about it," told Mr. Sholeh.
"Yes, Dad. Thank you," replied Mawar.

Why does Mawar call the library a mobile library?