The mass of the part of a metal rod that lies between its left end and a point x meters to the right is 2x2 kg. (See this example.) (a) Find the linear density when x is 2 m.
kg/m

(b) Find the linear density when x is 8 m.
kg/m

(c) Find the linear density when x is 9 m.
kg/m

Where is the density the highest?
At the right end of the rod.
At the left end of the rod.
In the middle of the rod.

Where is the density the lowest?
At the right end of the rod.
At the left end of the rod.
In the middle of the rod.