Helen's income tax liability for 2011 was$24,000. her self-employment tax was $4,000. helen projects that her income tax for 2012 will be $34,000 and her self-employment tax will be $6,000. helen will have $4,000 of income tax withholdings in 2012. helen makes estimated payments of $3,000 on april 15,2012; $5,000 on june 8,2012; $5,000 on september 15, 2012; and $4,000 on january 3,2013. helen files her return and pays the tax due on march 21,2013. compute helen's estimated tax underpayment for each quarter (if any) and indicate the time period for the underpayment penalty for each payment.