Sandra Bullock's romantic comedy 'The Proposal' finished No. 1 at the weekend box office with $34.1 million in estimated ticket sales.

In 'The Proposal,' Bullock plays a pushy boss who forces her young assistant -- played by Ryan Reynolds -- to marry her so she can keep her U.S. visa status and avoid being deported to Canada.

Dropping to No. 2 this weekend with $26.9 million was 'The Hangover,' the quirky comedy starring Bradley Cooper, Ed Helms, Zach Galifianakis and Heather Graham.

Coming in third was the Disney/Pixar collaboration 'Up,' with $21.3 million, followed in fourth by the comedy 'Year One,' which debuted with $20.2 million.

'Year One' stars Jack Black and Michael Cera as a couple of inept cavemen who are banished from their primitive village and attempt to embark on an epic journey through the ancient world. Instead, they discover a whole new world outside their prehistoric village.

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