Please help. I do not understand

The storage shed shown below is the shape of a half-cylinder of radius 7' and length I. {a} |What ihe volume of the shed? volume 2| | (bl The shed is filled with sawdust whose density.r {massfunit volume] at any point is inversely proportional to the distance of that point from the floor. That is, it the constant of proportionality is k, and y is the distance from the bottom of the shed, the density of the sawdust in the k shed at height 3,: is given by . y E! Find a, b, and y) so that the mass of the sawdust in the shed is given bvf y) dy. a (a) What is the volume of the shed? volume = (b) The shed is filled with sawdust whose density (mass/unit volume) at any point is inversely proportional to the distance of that point from the floor. That is, if the constant of proportionality is k, and y is the distance from the bottom of the shed, the density of the sawdust in the k shed at height y is given by y Find a, b, and f(y) so that the mass of the sawdust in the shed is given by [f(y) dy. 0 b= f(y)