PLEASE HELP!

Number the events in the order in which they occurred. Use the same number for events that happened at the same time. Three events have been numbered for you.

_____ fidel castro seals off the boatlift after about 125,000 cuban refugees had entered the united states.
_____ a major accident occurs at three mile island nuclear power plant near harrisburg, pennsylvania.
_____ soviet troops invade afghanistan.
_____ carter won a very close presidential election.
_____ the american hostages in iran are released.
_____ iranian students storm the american embassy in tehran and take fifty-two americans hostage.
_____ carter presents the national energy plan, aimed at resolving the energy crisis.
_____ an egyptian-israeli peace treaty is signed at the white house.
_____ ronald reagan takes the oath of office.
_____ carter orders cuban refugees moved to federal prisons to await removal hearings.
_____ islamic fundamentalists force shah mohammed reza pahlavi to flee iran.
_____ cuban refugees begin leaving from mariel harbor, en route to florida.
_____ carter signs second strategic arms limitation treaty.