abstract, fractal, complex
little joe, rocket, launcher
jatropha gossypiifolia, bellyache bush, cotton-leaf physic nut
prism, light, spectrum
bulb, light, energy
math work, mathematics, formulas
light bulb, brain, background
pulley, simple machine, machine
worm hole, space, science
light bulb, pattern, wallpaper
drop of water, nature, drop
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