ans = sqrt((1-4)^2 + (3-5)^2 + (4+2)^2) = sqrt((-3)^2 + (-2)^2 + 6^2) = sqrt(9 + 4 + 36) = sqrt(13 + 36) = sqrt(49) = 7
ans = sqrt((1-4)^2 + (3-5)^2 + (4+2)^2) = sqrt((-3)^2 + (-2)^2 + 6^2) = sqrt(9 + 4 + 36) = sqrt(13 + 36) = sqrt(49) = 7