Two particles having charges of 0.600{\rm nC} and 5.40{\rm nC} are separated by a distance of 1.70{\rm m} .
1) At what point along the line connecting the two charges is the net electric field due to the two charges equal to zero?
2) Where would the net electric field be zero if one of the charges were negative? Enter your answer as a distance from the charge initially equal 0.600{\rm nC} .