The graph is a rectangle. The lower limit of the graph is 6 and the upper limit is 12, because the distribution is uniform. The base length is 12-6=6. The height is 1/6, the same probability for all lengths. The area of the rectangle is 1 including all probabilities. The graph can be represented by a piecewise function f(x)=
{ 1/6 | 6≤x≤12
{ 0 | x<6 or x>12
Answer d is probably applicable.