Marathon Puts Beijing Air To The Test  In Beijing, the first
major test of the city's air quality was under way Sunday with
the women's marathon.    This is Weekend Edition from NPR News.
I'm Robert Smith. It might be hard to tell from the news, but
Michael Phelps wasn't the only athlete with a remarkable
achievement to report this morning. Sure, he's won his eighth
gold medal in this Olympics, broken seven world records, and is
being called by some "the greatest Olympian of all time," but
remember, he's a young man.  Now, consider Romania's Constantina
Tomescu, who took gold in the women's marathon. She's a 38-year-
old mom who made it look easy. NPR's Frank Langfitt reports.
FRANK LANGFITT: It's Sunday morning, and I'm standing in the
middle of Tiananmen Square. The marathon is just about to begin.
And it looks like a good day for the race, much better than
Chinese officials probably could have hoped for. It's overcast.
It's probably in the low 70s. There had been a lot of concern
about heat and smog for th