Which of the following experimental observations proved that the idea of matter and mass being evenly distributed in an atom was flawed? a. less than 1% of the alpha particles went un-deflected through the gold foil. b. less than 1% of the alpha particles were deflected by angles greater than 90°.c. the beam from the negative electrode was deflected by electrically charged rods. d. the beam from the negative electrode cast a shadow on the positive electrode.