Use the following table to calculate the train's average velocity during part B of the train ride.

60km/hr due east

Explanation:

Given parameters:

Displacement = 60km East

Start time  = 10am

End time  = 11am

Unknown:

Average velocity  = ?

Solution:

The average velocity is the displacement divided by the time taken.

 For this journey, the time taken is;

              11am  -  10am  = 1hr

 So;  

 Average velocity  = = 60km/hr due east

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.