According to John Locke, why do governments exist?

Governments provide the parameters for everyday behaviour for citizens, protect them from outside interference, and often provide for their well-being and happiness.

an ethnic enclave is a geographic area with high ethnic concentration,

the answer is: must pay taxes on profits

since it is considered as a part of your income, profits from investments is eligible for tax payment.

the tax from your investment could be influenced by how long you decided to sell it. united states promotes keeping your investment for long term period. so, the tax rate for investments that you sell in less than one year is typically higher compared to investments that you sell in more than one year period.