71.
__________ is derived recently from living organisms and their metabolic products.

72.
According to the Stefan-Boltzmann law, the radiative energy emitted by one square meter of an object is equal to a constant multiplied by its temperature raised to the _______ power.

73.
The nation whose government is promoting large families because of an aging population and low fertility rate is

74.
_________ is the first country to have phased out the CFCs and HCFCs which are responsible for the depletion of the ozone layer.

75.
The pyramid of biomass is inverted in

76.
Which of the following is the major cause of pollution?

77.
Which of the following would be considered to be a biotic component of an environment?

78.
Bears are usually hunted and killed for their

79.
All the genes of a population is called

80.
Viable material of endangered species can be preserved by