The diagram shows a piece of apparatus used to determine the nature of the emissions from a radioactive source. The absorbers can be raised out of or lowered into the path of the radiation from the source to the detector. The apparatus is evacuated.
The table gives a set of results for a particular radioactive source.
Which types of radiation are being emitted by the radioactive source?
-particles only
-particles
-particles and -particles
-particles and 
-rays
