6. Two simple curves having angles of intersection of the tangents equal to 360 and 6845' respectively are joined to formed a compound curve where the P.T. of the first curve now becomes the P.C.C. of the compound curve. If the length of chord of the first curve is 472.14 m. and the length of chord of the second curve is 235.21 m., find the length of the long chord from the P.C. to the new compound curve. (LC=643.30 m.)