USA

Sales of existing homes fell 2.6 percent in June, more sharply than industry analysts expected, the National Association of Realtors reported Thursday. The median house price from a year ago dropped 6.1 percent to $215,000.

A two-hour interrogation video of Osama bin Laden's former driver was the main defense evidence Wednesday in his trial in Guantánamo Bay, Cuba. In the tape, made shortly after his November 2001 capture in Afghanistan, Salim Hamdan denies working for Al Qaeda.

The Navy sank plans for its once heralded "stealth destroyer" Wednesday when it ended a production run after just two of the $5 billion warships were built. The boat was designed to slip close to shore but was thought vulnerable to attack by land-based missiles.

Antismoking efforts received a $375 million boost Wednesday when New York Mayor Michael Bloomberg and Microsoft cofounder Bill Gates pledged that amount to fight what they called a global tobacco epidemic. The partnership will devote special attention to curbing tobacco use in China and India.

The Social Security Administra-tion unveiled a new online calculator this week that supplements annual mailings that estimate retirement benefits.

Greater participation in higher level math classes by girls likely explains why their scores equal those of boys on standardized assessment tests, according to a study released Wednesday by researchers at the Universities of California and Wisconsin.

Gender-neutral wording will be required in future Massachusetts legislation if a bill, initially approved by the state's House of Representatives Wednesday, passes. At least a half-dozen other states have already introduced such legislative language.