Which of the following statements are true about the open interval (0,1) and the closed interval [0,1]?

1. There is a continuous function from (0,1)onto[0,1].

2. There is a continuous function from [0,1]onto(0,1).

3. There is a continuous one-to-one function from (0,1)onto[0,1].

How to prove or disprove each choice?