een developed.Р6. In his research at Columbia University, Charles Townes worded with all of the following EXCEPT CР(A) stimulated emissionР(B) microwavesР(C) light amplificationР(D) a maserР7. In approximately what year was the first maser built? CР(A) 1917Р(B) 1951Р(C) 1953Р(D) 1957Р8. The word "emerged" in line 16 is closest in meaning to DР(A) increasedР(B) concludedР(C) eededР(D) appearedР9. The word "outlining" in line 17 is closest in meaning to DР(A) assigningР(B) studyingР(C) checkingР(D) summarizingР10. Why do people still argue about who deserves the credit for the concept of the laser? BР(A) The researcher's notebooks were lost.Р(B) Several people were developing the idea at the same time.Р(C) No one claimed credit for the development until recently.Р(D) The work is still plete.
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