Which technique does the author use to each excerpt to support her purpose?

Explanation:

By early afternoon, it is 105 degrees. Enrique’s palms burn when he holds on to the hopper. He risks riding no-hands. Finally, he strips off his shirt and sits on it. The locomotive blows warm diesel smoke. People burn trash by the rails, sending up more heat and a searing stench. Many migrants have had their caps stolen, so they wrap their heads in T-shirts. They gaze enviously at villagers cooling themselves in streams and washing off after a day of fieldwork and at others who doze in hammocks slung in shady spots near adobe and cinder-block homes. The train cars sway from side to side, up and down, like bobbing ice cubes.

—Enrique’s Journey,

Sonia Nazario

c. barbarians with unexpected intelligence