USAco, a domestic corporation, filed its return for year 1 on March 15 of year 2. The IRS is auditing USAco's year 1 return. USAco is recalcitrant and fails to respond to any request for information from the IRS, including the IRS's summons for information. If the IRS is concerned about the statute of limitations expiring without obtaining any information to make an assessment, the IRS will issue USAco:

		another summons.
		an information document request.
		a formal document request.
		a designated summons.