Answer:
12%
Step-by-step explanation:
Calculation for marginal tax rate
Using this formula
Marginal tax rate=Change in Tax / Change in Taxable Income
Let plug in the formula
Marginal tax rate=(2,570-1,970)/5,000
Marginal tax rate=600/5,000
Marginal tax rate=0.12*100
Marginal tax rate=12%
Therefore Arlene has a marginal tax rate of 12%