In a major vote of confidence for the planned Smithsonian National Museum of African American History and Culture, the Bill and Melinda Gates Foundation announced that it is donating $10 million to the museum. The Gates money will go toward the museum’s capital campaign for design and construction of its building along the National Mall. The total cost of the museum is said to be about $500 million, with half that amount coming from Congress and the rest to be raised by the museum. Groundbreaking for the 300,000-square-foot building is slated for 2012.