When a file has been opened using the ‘r’ mode specifier, which method will return the file’s contents as a string? + python?

What is a number system, and what is the total number of digits used in this system called? a number system is a system that uses different (options: a) numbers b) symbols c) codes d) digits e) alphabets) to represent different numbers. the total number of digits used in a number system is known as its (options: 1) processor 2) converter 3) radix 4) least significant digit 5) most significant digit)