Which three tasks can be performed using regular expression support in Oracle Database 10g？（）
- A it can be used to concatenate two strings.
- B it can be used to find out the total length of the string.
- C it can be used for string manipulation and searching operations.
- D it can be used to format the output for a column or expression having string data.
- E it can be used to find and replace operations for a column or expression having string data.