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illustration of wise man writing mathematical problems, solution concept
Theory and practice symbol. Wooden blocks with words 'Theory and practice' on a beautiful orange background. Businessman hand. Business, theory and practice concept. Copy space.
Quantum world, speed of light. Quantum mechanics, spectral shift. 3d illustration
The hand puts a wooden cube with the letter T from the word THEORY. The word is written on wooden cubes standing on the yellow surface of the table.
thinker philosophy line icon vector. thinker philosophy sign. isolated contour symbol black illustration

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