There is no way to know this answer given the information you have provided. The reason for this is that we do not know how many tax brackets there are, what the minimum and maximum incomes for each bracket are, or what the marginal rates in each bracket are.
For example, let's look at what Sandra's tax liability would be if you were using the rates for federal income tax. This year, parts of Sandra's income would be taxed at four different rates. The first $8,500 would be taxed at 10%. The next $26,000 would be taxed at 15%. The next $49,100 would be taxed at 25%. The remainder would be taxed at 28%.
To find her liability, you would multiply the first $8,500 by 10%, the next $26,000 by 15% and so on. You would then add all the results to get her total liability.