An informational message of 1.5 KB contains 3072 characters. How many characters are in the alphabet

An informational message of 1.5 KB contains 3072 characters. How many characters are in the alphabet with which this message was written?

There are 1024 bytes in 1 KB, therefore, 1.5 KB = 1536 bytes.
There are 8 bits in 1 byte, therefore 1536 bytes = 12288 bits.
Let’s determine how many bits of memory 1 character of the text takes. There are 3072 of them, so one character takes 4 bits.
If one character encodes 4 bits of a binary (binary) code, then it is possible to encode 2 ^ 4 = 16 states in total. Therefore, there are 16 characters in the alphabet of the message.
Answer: the alphabet used to write the message contains 16 characters.