The frequency of sunspots and related solar activity is ________
A) a 22 year cycle B) not a regular cycle C) an 11 year cycle D) a 7 year cycle
C
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The main product that brought India into the global economy in the late 1800s was
A. cotton B. gold C. steel D. rice
Wegener used all the following to provide evidence for continental drift except :
a) age of selected continental rocks. b) shape of continental margins. c) location of coral reef fossils. d) apparent polar wandering. e) seafloor magnetic pattern.
Reducing population growth rates in poor countries can be accomplished by ________
A) reproducing beyond replacement fertility B) economic disasters C) valuing the birth of a son D) education of women E) illness in infants
Why would astronomers have difficulty spotting a large incoming asteroid headed for Earth?
a. ?It remains in a fixed position in the sky as it comes in directly, so astronomers cannot see its trajectory. b. ?It comes in so fast that they do not have time to see it. c. ?It is dark before becoming heated in Earth’s atmosphere. d. ?It is not an important topic to monitor for most astronomers. e. ?It is simply too big to seem as if it is moving.