An association between air pollution and mortality in six U.S. cities.
There is mortality associated with air pollution in six U.S. cities.
Air pollution has no direct effect on humans.
A man with his daughter preparing an art piece.
It's not a shame.
A dog and person are at the beach along with other dogs.
No matter the obstacles in her way, she was an optimistic person.
The turtles are racing.
A snowboarder jumps down a hill.