51. Dactylology is the study of ____:
52. Demography deals with ____:
53. Dendrochronology is the study of ____:
54. Dendrology is the study of ______:
55. Dermatology is the study of ___:
56. Ecology is the study of ___:
57. Economics deals with ___:
58. What does Electrostatics study?
59. Embryology is the study of ____:
60. Endemiology is the study of _____: