The simplest life forms appeared on Earth by the time it was how old?
A) five million years
B) one billion years
C) 2.5 billion years
D) 3.5 billion years
E) 4.5 billion years
B
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A charged particle with mass m is suspended in the air by an upward-directed electric field E. What is the charge on the dust particle?
a. q = mgE b. q = mg/E c. q = E/mg d. q = Em/g
The melting point of silicate minerals is strongly dependent on the amount of silica it contains. The first minerals to melt are those with
What will be an ideal response?
An object placed 19.0 cm from a concave mirror produces a real image 12.7 cm from the mirror. If the object is now moved to a new position 27.0 cm from the mirror, where is the new image located as measured from the mirror?
a. 7.61 cm b. 10.6 cm c. 5.94 cm d. 18.0 cm e. 20.7 cm
Rocks solidified from molten material below ground are classified as ______________ igneous rocks
a. extrusive b. intrusive c. superior d. inferior