Which chemical family is composed almost entirely of man-made elements?
A) the actinides
B) the lanthanides
C) the halogens
D) all of the above
E) none of the above
A
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What causes magnetic stripes on the seafloor, such as those shown here?
A) Volcanic rocks in oceanic crust are covered by a variable thickness of sediment.
B) Some oceanic crust consists of volcanic rocks and some is composed of sediment.
C) Sometimes Earth's magnetic field points north and sometimes it points south.
D) Some volcanic rocks are formed in normal ways and others have pillows.
Meteorologists may blend the results of multiple models and put their own personal adjustments into a forecast
Indicate whether the statement is true or false
Which of the following is false regarding the Mediterranean classification?
A) Summers are hot. B) Seventy percent of the precipitation occurs in the winter months. C) Summers are influenced by shifting subtropical high cells. D) The bulk of precipitation occurs in the summer months.
The fundamental principle governing international aviation is that States have sovereign control over their own air space
Indicate whether the statement is true or false