A red flag with a diagonal white stripe indicates scuba diving.

And the alpha flag indicates that there is a diver inside.

SCUBA means Self Contained Underwater Breathing Apparatus.

Protists are eukaryotic organisms that cannot be classified as a plant, animal, or fungus. They are mostly unicellular, but some, like algae, are multicellular.

Kelp, or 'seaweed,' is a large multicellular protist that provides food, shelter, and oxygen for numerous underwater ecosystems.

Envelope is a letter holder for one letter and in the question it mean that it holds one letter. Eye is also a word which starts and end with E but has one letter in the middle.

RAM storage capacity is measured in bytes, kilo bytes, mega bytes, giga bytes,...

Presidential elections are held every four years, in years divisible by four, in which electors for President are chosen by the method in the country.