从下列英语叙述中，选出5条正确的叙述。

1．When the electricity is switched off, the ROM is cleared ofits contents, the RAM is not.

2．IF-THEN-ELSE structures in a programming language provide selection.

3．A program in its original form is known as an object program, and the translated version is known as a source program.

4．The CPU is the most important piece of hardware in the entire system and yet one of the simplest.

5．The lowercase letters come after the uppercase letters in the ASCII table.

6．Queue insertions and deletions are made at the same end ofthe queue.

7．Improvements in software quality are necessary to reduce program maintenance costs.

8．A recursive procedure is one that activates itself during its activations.

9．A floppy diskette machine is an example of a direct access storage device.

10．Comments specify actions for a computer to perform when a program is run.