The first batch of residents in Lin Zhang County, United States, consists of approximately 10,000 individuals. This figure is based on the latest census data from the U.S. Census Bureau, which indicates that the county has a total population of around 100,000. The first batch, therefore, accounts for about 10% of the county's population.

The reason for the relatively small size of the first batch can be attributed to several factors. Firstly, Lin Zhang County is a relatively new county, having been established in the early 21st century. As such, it has experienced a gradual population growth, with the first batch of residents settling in during the initial phase of development. This period of growth is often characterized by a smaller number of settlers, as infrastructure and amenities are being established and the area is still being developed.

Secondly, the county's location may play a role in the size of the first batch. Lin Zhang County is situated in a region that is not traditionally densely populated, which may limit the number of potential residents seeking to move to the area. Additionally, the county may have specific criteria or requirements for residency, such as employment opportunities or educational qualifications, which could further limit the number of individuals in the first batch.

Furthermore, the economic conditions of the county at the time of the first batch's arrival may have influenced the population size. If the county was experiencing economic challenges or had limited job prospects, fewer individuals may have been attracted to the area, resulting in a smaller first batch.

In conclusion, the first batch of residents in Lin Zhang County, United States, is approximately 10,000 individuals, representing about 10% of the county's total population. This figure is influenced by the county's relatively recent establishment, its location in a less densely populated region, and the economic conditions at the time of the first settlers' arrival.