Final answer:
This is an example of the equitable goal of an effective tax system.
Step-by-step explanation:
This is an example of the equitable goal of an effective tax system. An equitable tax system ensures that tax burdens are distributed fairly among the population. In this case, Rhianna's tax deductions are being deducted from her pay, which means that she is contributing to government revenue based on her earnings. This ensures that individuals with higher incomes pay more in taxes compared to those with lower incomes.