Please help! I don't know what I'm doing wrong

The figure below shows three small, charged spheres, all lying along the horizontal axis. Sphere A, at left, has a 6.90 nC charge. Sphere B has a 1.70 nC charge and is 3.00 cm to the right of A. Sphere C has a -2.10 nC charge and is 2.00 cm to the right of B. Find the magnitude (in N) and direction of the net electric force on each of the spheres. + 3.00 cm 2.00 cm Net Force on A magnitude X Draw the forces on A due to both B and C. What are the signs of the charges? How does this affect the directions of the forces? From Coulomb's law, what is the magnitude of each force? Add the forces as vectors to get the net force. Be careful with units and signs. N direction toward the left Net Force on B magnitude 2.810-7 X Draw the forces on B due to both A and C. What are the signs of the charges? How does this affect the directions of the forces? From Coulomb's law, what is the magnitude of each force? Add the forces as vectors to get the net force. Be careful with units and signs. N direction toward the right v X Draw the forces on 8 due to both A and C. What are the signs of the charges? How does this affect the directions of the forces? Add the forces as vectors to get the net force. What direction is the net force? Net Force on C magnitude 1,32e-6 X Draw the forces on C due to both A and B. What are the signs of the charges? How does this affect the directions of the forces? From Coulomb's law, what is the magnitude of each force? Add the forces as vectors to get the net force Be careful with units and signs. N direction toward the left v