What are the four classes of fire according to nfpa?

According to the NFPA, the five classifications of fire are:

"Class A: result from ordinary combustible materials, including wood, cloth, paper, and many plastics.

Class B: burn in flammable liquids, combustible liquids, petroleum greases, oils, alcohols, and flammable gases.

Class C: involve energized electrical equipment.

Class D: fires in combustible metals, such as magnesium, titanium, zirconium, sodium, lithium, and potassium.

Class K: fires in cooking appliances that involve combustible cooking media, such as vegetable or animal oils and fats"

i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.

bro these r easy u may have to do them urself bro. lol jk the answer is two for nimber one, and for question number two sahel boi xd have fun get rekt m8