1. The problem is attached in a picture. I've done it five times and keep getting it wrong. The correct answer is also displayed in the picture. Thank you for any help. 2. Fg=Gm_1m_2/r^2 3. I calculated Fg between AB and BC (they are equal). So Fg=(6.67*10^-11)(4)(4)/(.10)^2=1.067*10^-10. Then I drew a triangle (also attached). I labeled the point in between B and C the center of my axis. So when I calculated the sum of the forces in the x direction I got 0. In the y direction the sum of the forces is 2*1.067*10^-10*sin60. I did that and got 2.13*10^-10. Why isn't that the right answer?