Color, the other answers arent changing the substance into something different
Answer:
I' really don't know I'm sorry
The uranium within these items is radioactive and should be treated with care. Uranium's most stable isotope, uranium-238, has a half-life of about 4,468,000,000 years. It decays into thorium-234 through alpha decay or decays through spontaneous fission.
The straight horizontal line shows us that the object is moving at a constant speed
