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249. A_____ has taught us what atoms are made up of and how powerful the atom bomb is.

249. A_____ has taught us what atoms are made up of and how powerful the atom bomb is.

 A.seaman                 B. salesman               C. naturalist                    D. Scientist

A_____ has taught us what atoms are made up of and how powerful the atom bomb is.

   A. seaman            B. salesman               C. naturalist             D. scientist

A_____ has taught us what atoms are made up of and how powerful the atom bomb is.

A. seaman　　 B. salesman　　　 C. naturalist　　　 D. scientist