How many bits are used to represent Unicode, ASCII, UTF-16, and UTF-8

Question :How many bits are used to represent Unicode, ASCII, UTF-16, and UTF-8
characters? (CoreJava)
Answer :Unicode requires 16 bits and ASCII require 7 bits. Although the ASCII
character set uses only 7 bits, it is usually represented as 8 bits. UTF-8
represents characters using 8, 16, and 18 bit patterns. UTF-16 uses 16-bit
and larger bit patterns.