Which activity is the best demonstration of j. j. thomson’s use of creativity in his work? making observations in his experiment interpreting the results of his experiment assembling the apparatus for his experiment taking notes on joseph proust’s work

The correct answer is making observations in his experiment.

In his cathode ray tube experiment J. J. Thomson proved that the cathode rays are indeed negatively charged particles. He then went on to calculate charge-to-mass ratio of the electron. J. J. Thomson’s pioneering work lest to the theory that the atomic structure is made up of charged particles.  

the correct answer is:

a. formation of precipitation