Hello...my name is XXXXX XXXXX I am a Certified Public Accountant. I look forward to assisting you with your tax question.
I am assuming your installment agreement relates to a tax year prior to 2011. If that is the case, then yes you would still be responsible for the installment agreement and the amount due for the 2011 taxes. If you are unable to pay the $35,000 taxes for 2011, you would be able to work out a 2nd installment agreement with the IRS or request them to combine the 2 into one monthly payment.
Yes...you can have 2 installment agreements with the IRS but you may want to consolidate the 2 into one agreement to make it easier for you
Yes...you can request the 120 day extension from the IRS. When you make the payment for the 2011 taxes you will want to be sure to mark the tax year that the payment should be applied to...