51.

The polar regions of earth cannot support forest growth because

A. the growing season is short in these areas B. the ground is often frozen or snow or ice covered
C. the rainfall is very low D. All of these factors.
Answer:D
Explanation: No answer description available for this question.

52.

The part of the earth and thin layer of air above its surface, which support life on earth, are referred to as

A. stratosphere B. ionosphere
C. biosphere D. mesosphere
Answer:C
Explanation: No answer description available for this question.

53.

The ridges of the waves are where the jet stream of waves closes to the

A. poles B. equator
C. prime meridian D. None of the above
Answer:A
Explanation: No answer description available for this question.

54.

The rate at change of temperature is called

A. temperature difference B. temperature gradient
C. isotherm D. None of the above
Answer:C
Explanation: No answer description available for this question.

55.

The rate of infiltration normally declines rapidly during the early part of rainstorm event and reaches a constant value after several hours of rainfall. The factors responsible for this phenomenon are I.the filling of fine soil pores with water, which reduces capillary forces II.moistened soil, clay particles to swell and reduce the size of pores III.raindrop impact breaking up with soil clumps, splashing fine particles into pores

A. I, II B. I, III
C. II, III D. All of the above
Answer:D
Explanation: No answer description available for this question.