Two metal rods in a factory are oppositely charged and placed 8.9 cm apart. One rod has a charge of +7.5 x 10^-7 C and the other has a charge of -5.1 x
10^-5 C. What is the force between the rods?

the total distance that martina travels that day is

(distance from home to mom's office) plus (distance from mom's office to school)

plus (distance from school to library) plus (distance from library to friend's house)

plus (distance from friend's house to martina's house).

(we don't know what any of these distance actually is.)

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.