The maximum velocity at the tip of growing dendrite occurs when ______ (r* is the critical radius)

The maximum velocity at the tip of growing dendrite occurs when ______

1.	The maximum velocity at the tip of growing dendrite occurs when ______ (r* is the critical radius)
A.	R = 2r*
B.	R = 3r*
C.	R = r*
D.	R = 4r*
Answer» B. R = 3r*

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The maximum velocity at the tip of growing dendrite occurs when ______ (r* is the critical radius)

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