Solve the problem.The flow of blood in a blood vessel is faster toward the center of the vessel and slower toward the outside. The speed of the blood is given by  where R is the radius of the blood vessel, r is the distance of the flowing blood from the center of the blood vessel, and p, v, and L are physical constants related to the pressure and viscosity of the blood and the length of the blood vessel. If R is constant, we can think of V as a function of r:  The total blood flow Q is given by 

src="https://sciemce.com/media/4/ppg__tttt0604190834__f1q6g3.jpg" alt="" style="vertical-align: -23.0px;" /> Find Q for a blood vessel of radius R = 0.4 mm.



A.  
B.  
C.  
D.  

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Answer: C

Mathematics