What was the historical significance of Wundt, James, and Freud?

Wundt, James, and Freud laid the foundations of psychology.

Explanation:

Let's begin with Wilhelm Wundt:

Wundt is recognized as the "Father of Psychology", and created the first experimental laboratory to study psychology. In Wundt's lab, he would sit someone down, bounce a ball against a machine, and tell them to push a button when they heard the ball bounce; then recording their sensory stimulus reaction time. There are two key things to note about Wundt: Structuralism and introspection. Wundt wanted to break down the human mind like a periodic table (i.e. basic conscious elements), and this thought process later became known as structuralism, which by definition, was the study of elements of consciousness. Wundt trained his participants to analyze their thoughts. This was the process of introspection; literally meaning "to look inward."

Now, for William James:

James is recognized as the "Father of American Psychology", writing the first psychology textbook: The Principles of Psychology. James wanted to know how thinking adapts. James was largely influenced by Charles Darwin's theory of natural selection, and is responsible for the theory of functionalism, psychology's second school of thought.

Finally, Sigmund Freud:

Freud was responsible for one of the modern approaches to psychology: psychoanalysis. The approach of psychoanalysis mainly focuses on how our unconscious thoughts determine our behavior, and how our unconscious mind most influences our thought.

they deliver oxygen to the blood

i'd say that the moon rock is about 2.2 billion years old.