13. 一直線 L 與拋物線y2=8x 交於 A、B 兩點，且直線 L 與拋物線所圍成之面積為定值，則 A、B 中點所形成之軌跡方程式為何？

⑶ This insurance indemnifies the Assured, in respect of any risk insured herein, against liability incurred under any Both to Blame Collision Clause in the contract of carriage. In the event of any claim by carriers under the said Clause, the Assured agree to notify the insurers who shall have the right, at their own cost and expense, to defend the Assured against such claim.