Assertion: gamma ray's source | /r/HasProperty | natural
Facets:
Source sentences:
text: Whether the source of radiation is natural or man-made, whether it is a large dose of radiation or a small dose, there will be some biological effects.
text: Whether the source of radiation is natural or man-made, whether it is a large dose of radiation or a small dose, there will be some biological effects.
text: The sources of radioactive pollution can be natural or man-made.