Find the Mass of a Cylindrical Rod with a Radius $\rho ( x ) = 10 - 0.05 x$

Multiple Choice

Find the mass of a cylindrical rod with a radius of 5 centimeters and a length of 30 centimeters, made of two metals in such a way that the density of the rod × centimeters from the left end is $\rho ( x ) = 10 - 0.05 x$ grams per cubic centimeter.

A) 6525 $\pi$
B) 6975.5 $\pi$
C) 6937.5 $\pi$
D) 6637.5 $\pi$