When pillars are left during coal mining, subsidence occurs:
a. during mining
b. shortly after mining
c. many years after mining
d. no subsidence takes place with this mining technique
c
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If when jumping you bend your knees to increase the contact time of landing by 5 times, the average force your body experiences can be reduced by about
A. 2.5 times. B. up to 10 times. C. 5 times. D. none of the above
Which one of the following has been decreasing over the past several decades?
A) Mean global temperature B) Methane levels in the troposphere C) Sea levels D) pH of the world's oceans
The Tropic of Capricorn refers to
A) that parallel that is 23.5° south latitude. B) the location of the subsolar point on September 22. C) the parallel that is the farthest northern location for the subsolar point during the year. D) that parallel that is 66.5° south latitude.
Briefly explain how airflow aloft aids the formation of cyclones at the surface
What will be an ideal response?