A long line of charge with uniform linear charge density λ1 is located on the x-axis and another long line of charge with uniform linear charge density λ2 is located on the y-axis with their centers crossing at the origin. In what direction is the electric field at point z = a on the positive z-axis if λ1 and λ2 are positive?
A-) The positive z-direction
B-) All directions are possible parallel to the x-y plane
C-) The negative z-direction
D-) Halfway between the x-direction and the y-direction
e-) Cannot be determined

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