Which of the following statements gives the main reason that night-time radio broadcasts can be sent over long distances?
A. Radio waves propagate more efficiently through cooler, high-density air.
B. Radio stations put out more power at night.
C. The low D-level region of the ionosphere is weaker at night.
D. There is less interference because many radio stations do not broadcast at night.
Answer: C
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Doppler radar aids tornado detection by detecting ________
A) wind gusts at ground level B) ice particles in clouds C) high pressure in a region D) motion within clouds.
Which Köppen climate type (or types) is most closely associated with regions of the tropical scrub and the tropical savanna biomes?
Using the global map of biome distribution (Map T-30 in the back of the Lab Manual), the map of climate distribution (Map T-29), the maps of global temperature (Maps T-28a and T-28b), the map of global precipitation (on the inside front cover of the Lab Manual), as well as information about Köppen climate types from Exercise 23, answer the question. What will be an ideal response?
The principle of Uniformitarianism assumes that physical processes that operate in the modern world also operated in the past, at quite different rates.
a. true b. false
How is a crater different from a caldera?
What will be an ideal response?