31. Who discovered the concept of nuclear fission?
a) Otto Hahn and Fritz Strassmann
b) Marie Curie
c) Pierre Curie
d) Antoine Becquerel
32. Who discovered the concept of superconductivity?
a) Heike Kamerlingh Onnes
b) Marie Curie
c) Pierre Curie
d) Antoine Becquerel
33. Who discovered the concept of the laser?
a) Theodore Maiman
b) Marie Curie
c) Pierre Curie
d) Antoine Becquerel
34. Who discovered the concept of the photoelectric cell?
a) Alexander Graham Bell
b) Marie Curie
c) Pierre Curie
d) Antoine Becquerel
35. Who discovered the concept of the Geiger counter?
a) Hans Geiger
b) Marie Curie
c) Pierre Curie
d) Antoine Becquerel