A museum conservator investigates two stone carvings. Carving R is exposed to gamma radiation from a sealed source outside the carving. The source is then returned to storage. Radioactive dust has settled on the surface of carving S and has not been cleaned away.
Which statement about handling the carvings now is correct?
Carving R can be handled safely, but carving S keeps emitting radiation while the dust remains on it.
Carving R can be handled safely, and carving S stopped emitting radiation when the source was stored.
Carving R must be washed to remove radioactive material, but carving S is safe as its dust is only on the surface.
Carving R keeps emitting the gamma radiation it absorbed, and carving S keeps emitting radiation from its dust.