The answer to this puzzle is:
W. AMADEUS. M - a famous class(ical) composer.
Puzzle 1:
To solve this, note that FRA and GIN are:
3-letter country abbreviations for France and Guinea. These two countries have triband flags, France's being blue-white-red and Guinea's being red-yellow-green. If we join these coloured dots in this order, we see a 'W' traced out:
Puzzle 2:
The moon and sun icons here have connotations with:
Monday and Sunday (these days of the week are named after them). Note then that beneath these symbols we have seven rows of boxes. Moreover, the number of boxes in these rows correspond to the number of letters in the names of the seven days of the week in English.
Note next that each 'thumbs-up' bullet point is surrounded by a number of bars. Count these up and index into the corresponding day of the week to extract a letter. This yields:
MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY and SUNDAY.
Together, this gives the letter set MSEUDAA, which is an anagram of AMADEUS.
Puzzle 3:
This is a rebus of sorts that requires a few steps to it:
Here, 'Pr' represents 'prime'. The 9th prime (indicated by the substring '9') is 23. The 23rd letter of the English alphabet is 'W', and rotating this 180 degrees (as suggested by the arrow) turns our 'W' into an 'M'.
This explanation clarified in comments by the OP, below, following my initial chemistry-connected suggestion neglected to use a part of the rebus.