What are key questions about chapters 17-21 in The Grapes of Wrath?

In looking for a means to review the important concepts and events depicted in John Steinbeck's The Grapes of Wrath, I would expect there are several important questions one might ask him- or herself in Chapters 17-21.

First, I believe it would be important to ask, "How is the importance of family in evidence in these chapters?" Family here applies not only to those related by blood, but also to the extended family made up of people who have joined together to travel westward in hopes of finding a better life.

Another important question would be directed to how the lawmakers fail to create and follow laws that protect everyone: "How are the laws followed by the police unlawful?" The laws established are only for the select few: those with land and money.

Another question might be, "Who would you describe as the "haves" and the "have-nots" in this story, and why is this distinction important? Obviously those who "have" do not want to share with the migrant workers (the "have-nots").

Another question might address financial issues: "How do the wealthy and the bankers control the economy in California, which directly affects the migrant workers who are trying to start a new life?" Keeping wages low and costs high controls the economic progress of the migrant workers; these issues also run small farmers out of business as well.

What are significant lines in chapters 17-21 of The Grapes of Wrath?

Some significant lines in John Steinbeck's The Grapes of Wrath, found in Chapters 17 through 21, are included below.

Ma senses that her family is falling apart as the story progresses; a significant piece of writing is found in Chapter 18.

The woman leaned down over Granma's face, and she seemed almost to sniff. Then she turned to Ma and nodded quickly, her lips jiggled and her jowls quivered. "A dear soul gonna join her Jesus," she said.

Ma cried, "That ain't so!"

Ma is struck considerably hard when one of their number leaves or passes. She does not want to believe that Granma might be leaving them, though in time, this does happen again.

Later in Chapter 18, facing loss is again expressed:

Sairy lay on the mattress, her eyes wide and bright...Her low, beautiful voice went on, 'I wanted us to go, I knowed I wouldn' live to the other side, but he'd be acrost anyways...He don't know. He thinks it's gonna be all right...I ast you to come to say a prayer.'

'I ain't a preacher,' he said softly.

'I want you should say [a prayer] for me.'

'Maybe you'll res' a few days and'  then come on.'

She shook her head slowly from side to side. 'I'm jus' pain covered with skin...'

Sairy knows that she is dying of cancer, but she has told no one, not even her husband.

Another plight the migrant farmers face is presented again in Chapter 19.

Three hundred thousand in California and more coming. And in California the roads full of frantic people running like ants to pull, to push, to lift, to work. For every manload to lift, five pairs of arms extended to lift it; for every stomatchful of food available, five mouths open.

Here, again, the reader is struck with an image of the hundred and thousands of people flowing in from the Midwest, vying for jobs. There are only so many jobs, and so many more people in need than jobs available to them.  Getting work does not simply infer that people want a job, but that the work is all that stands between the people and the starvation of their families.