Simplify the following text for a Grade 6 native English-speaking person.
Original: Terminal 5 was officially opened by Queen Elizabeth II on 14 March 2008 and opened to passengers on 27 March 2008 .
Simplified: The site covers 12.14 k. Terminal 5 was officially opened by Queen Elizabeth II on 14 March 2008 and opened to passengers on 27 March 2008 .