1. How do scientists know that there is the same amount of freshwater on Earth as there has always been?
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The solstices and equinoxes, and the number of hours of daylight associated with each, are major factors in the seasons. use the drop-down menus to identify the month when each of these events occurs. the winter solstice in the northern hemisphere: an equinox in both hemispheres: the summer solstice in the northern hemisphere:

In the figure, polygon abcd is transformed to create polygon a′b′c′d′. this transformation is a by a factor of .

Sink holes may eventually for to join a. wide valleys b. zone of aeration c. dripstones d. aquifer