Answer
See the explanation below.
Work Step by Step
a) The meaning of the integral is the chance the college female student that is randomly chosen weighs less than 130 lbs.
b) $D = \int_{-\infty}^\infty x*f(x) dx$
Note: the integral bounds can also be from 0 to positive infinity because the graph is zero for negative x values.
c) Since all the probabilities should add to 1 as they don't overlap, the median would be 1/2 way in between or $$D = \int_{u_0}^\infty x*f(x) dx=1/2$$ where $u_0$ is the median.
