Mike is organizing 10K run race for his school activity. Mike would like to place a volunteer somewhere between the 1 mile marker and 5 mile marker. Suppose an incident will occur at position X between the 1 mile marker and 5 mile marker and X is a random variable with PDF of f(x)=5/4x2 for1x5.

At what point B should the volunteer be in order to minimize the expected distance, E[|X B|], to the incident?