Which tasks can be performed using SQL functions that are built into Oracle database?

Which tasks can be performed using SQL functions that are built into Oracle database?
(Choose three.)

A.
removing trailing, leading, and embedded characters from a character string

B.
finding the remainder of a division

C.
adding a number to a date for a resultant date value

D.
comparing two expressions to check whether they are equal

E.
checking whether a specified character exists in a given string