Read the following columns and answer the questions.

April 14 - ON THIS DAY

1865

President Abraham Lincoln was shot while watching a play at Ford's Theater in Washington, DC. He died a short while Later, and the U.S. was thrown into chaos. The assassin was John Wilkes Booth, an American actor. Most Americans believe Booth acted alone. But actually, there were eight others in a conspiracy, targeting not only the President, but the Vice President and Secretary of state.

1912

The Titanic sank. The Titanic was built to be a fine example of modern technology. It was the Largest ship ever made. It was considered unsinkable. It was sailing on its very first trip from England to New York with many rich and famous people on board. The Titanic hit a huge piece of ice near Newfoundland, Canada. The ship sank to the bottom of the Atlantic Ocean. More than one thousand five hundred of its two thousand, two hundred passengers died.

1981

The National Aeronautics and Space Administration, NASA, launched the Columbia from Kennedy Space Center on April 12th, 1981. The nation watched on television. The shuttle launch marked the completion of goals set nearly ten years earlier. Columbia raced into the sky and into history. Its two million five hundred thousand moving parts made it the most complex and costly vehicle ever made. The spacecraft would repeat its first success twenty-seven times.

How many times did Columbia go on its successful mission?