The 2010 annual report of CACCo. includes the following footnote related to its marketable debt securities (all classified as trading securities):

	December 31, 2010
($ in millions)	Amortized Cost				Gross Unrealized Gains				Gross Unrealized Losses				Fair Value
Marketable debt securities
Mortgage-backed securities:
Agency	$	190,809			$	640			$	(1,963	)		$	189,486
Agency-collateralized mortgage obligations	8,296				85				(51		)		8,330
Commercial	12,594				21				(293		)		12,322
Non-agency residential	1,863				181				(31		)		2,013
Total mortgage-backed securities	213,562				927				(2,338		)		212,151
U.S. Treasury and agency securities	48,800				204				(752		)		48,252
Non-U.S. securities	6,372				13				(3		)		6,382
Other taxable securities, substantially all asset-backed securities	10,573				64				(23		)		10,614
Total taxable securities	279,307				1,208				(3,116		)		277,399
Tax-exempt securities	17,272				72				(184		)		17,160
Total marketable debt securities	296,579				1,280				(3,300		)		294,559

Part A - What amount will CACCo. report for marketable debt securities on the balance sheet for December 31, 2010?

Part B - Calculate the net unrealized gain/loss for 2010.