Could you explain how to find/ use calculations and fill out part b table

Jeremy (unmarried) earned $100,000 in salary and $6,000 in interest income during the year. Jeremy's employer withheld $10,000 of federal income taxes from Jeremy's paychecks during the year. Jeremy has one qualifying dependent child (age 14) who lives with him. Jeremy qualifies to file as head of household and has $23,000 in itemized deductions. (Use the tax rate schedules, Tax rates for Net Capital Gains and Qualified Dividends.) Required: a. Determine Jeremy's tax refund or taxes due. b. Assume that in addition to the original facts, Jeremy has a long-term capital gain of $4,000. What is Jeremy's tax refund or tax due including the tax on the capital gain? c. Assume the original facts except that Jeremy has only $7,000 in itemized deductions. What is Jeremy's tax refund or tax due? Complete this question by entering your answers in the tabs below. Assume that in addition to the original facts, Jeremy has a long-term capital gain of $4,000. What is Jeremy's tax refund or tax due including the tax on the capital gain? Schedule Z-Head of Household \begin{tabular}{|c|c|l|} \hline If taxable income is over: & But not over: & \multicolumn{1}{c|}{ The tax is: } \\ \hline$10 & $15,700 & 10% of taxable income \\ \hline$15,700 & $59,850 & $1,570 plus 12% of the excess over $15,700 \\ \hline$59,850 & $95,350 & $6,868 plus 22% of the excess over $59,850 \\ \hline$95,350 & $182,100 & $14,678 plus 24% of the excess over $95,350 \\ \hline$182,100 & $231,250 & $35,498 plus 32% of the excess over $182,100 \\ \hline$231,250 & $578,100 & $51,226 plus 35% of the excess over $231,250 \\ \hline$578,100 & - & $172,623.5 plus 37% of the excess over $578,100 \\ \hline \end{tabular} Tax Rates for Net Capital Gains and Qualified Dividends *This rate applies to the net capital gains and qualified dividends that fall within the range of taxable income specified in the table (net capital gains and qualified purpose)