Since the taxable part of a Traditional IRA to Roth conversion is taxed as ordinary income at your margional tax rate, nobody that does not know ALL of your income, filing status, deductions, etc. could answer that question. Everything on a tax return can affect the final taxable amount.
$3,000 tax on $20,000 would be about 15% which is fine if you are in the 15% tax bracket but if you have more income to enter then that will probably go up.