完型填空（每空1分，共5分）The bill of lading by itself is not a contract of carriage as it is signed only by the carrier. However, it provides（ ① ）. It serves as a receipt for goods delivered to the carrier. Besides, the bill of lading serves as a document of title enabling the goods to be transferred from the shipper to the consignee or any other party by endorsement.The sea waybill is the replacement of the traditional （ ② ）. The waybill is a non-negotiable document and made out to a （ ③ ） who is allowed, upon production of proper identification, to claim the goods without presenting the waybill.The （ ④ ） is issued by the carrier to enable the consignee to take delivery of the cargo from the vessel.The mate’s receipt is the receipt issued by the chief mate in the acknowledgement of the goods received on board which is subsequently exchanged for the（ ⑤ ）.

A． shipper

B．consignee

C．carrier

D．exporter

人们经常谈到的风化壳位于哪个地质层位得顶部？钻遇这个层位时通常会出现什么复杂情况？