Final answer:
One important event was the completion of the First Transcontinental Railroad, connecting the railroad from coast to coast. Another important event was the construction of other major rail lines that expanded transportation and connected different regions of the country.
Step-by-step explanation:
One important event that happened as the Central Pacific crew worked on the railroad was the completion of the First Transcontinental Railroad. On May 10, 1869, the eastbound Central Pacific and westbound Union Pacific crews met at Promontory Point, Utah, connecting the railroad from coast to coast. This was a significant achievement in transportation and allowed for increased commercial activity and development in the West.
Another important event was the construction of other major rail lines following the completion of the First Transcontinental Railroad. Congress approved land grants that spurred the construction of rail lines such as the Atchison, Topeka, and Santa Fe line, the Southern Pacific, the Northern Pacific, and a fifth transcontinental line connecting Seattle with the Great Lakes. These rail lines further expanded transportation and connected different regions of the country.