A thin cylindrical rod is placed along the x-axis of a coordinate system. It has a linear mass density (x) that is not constant over the rod. In other words, some parts of the rod are heavier (per unit length) than others. If the rod stretches from x=A to x=B, which of the following gives the location of the center of mass of the rod? Select one: a. xCM=BAx(x)dx(BA) b. xCM=BAx(x)dxBA(x)dx c. xCM=BAxdx(BA) d. xCM=BAx2(x)dxBA(x)dx