Final answer:
The cattle industry boom in the West led to increased profitability, rampant speculation, and the spread of the American way of life in the region.
Step-by-step explanation:
The cattle industry boom had a significant impact on the economy of the West. With the completion of the transcontinental railroad and subsequent rail lines, cattle ranchers realized the profitability of rounding up wild steers and selling them in the East. This led to rampant speculation in the cattle industry, creating fortunes for some and causing the emergence of big business in ranching. Middle-class families moved to the West, built thriving cities, and contributed to the spread of the American way of life.