I need help with 5.17. I'm trying to learn how to do problem 5.17.

5.17 Uranium in the Earth's crust. The American Mineralogist (October 2009) published a stud).r of the evolution of ura- nium minerals in the Earth's crust. Researchers estimate that the trace amount of uranium l" in reservoirs follows a uniform distribution ranging between I and 3 parts per million. a. Find E ( Y} and interpret its value. b. Compute P(2