I think A.weathering, is the best possible answer
The correct answer is B. The tendency of molecules to move toward areas of lower concentration is called diffusion. This happens when there is a concentration gradient. This is described by the Fick's laws of diffusion. Diffusion is the net movement of molecules from a higher concentration to lower concentration to achieve equilibrium.
Actually, there are four kinds of reptile motion:
Concertina - vermiform. Circular muscles around the snake squeeze the front of the snake's body out long, then the latter half is pulled forward.
Rectilinear crawling - Belly scutes are moved forward individually in a wave-like motion.
Side-winding - Snake's version of "walking". Use by several species to move over fluidic substrates, such as sand.
Lateral undulation - Most common form of movement. Snake presses on alternating pressure points to force body forward (or backward)
(taken from a user on Yahoo from Correct Answers)
1) <span>NaNO3 and H2O - no reaction , it is dissolution
2) no hydrogen to make water
3) </span><span>Fe(OH)3 (base) and H2SO4(acid))
base +acid ----> salt +water
4) </span><span>Li2O and Ba(OH)2
basic oxide and base ----> no reaction
so Answer number 3)
</span> 2Fe(OH)3 +3 H2SO4 ------> Fe2(SO4)3 + 6H2O<span>
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