12. How many life buoys __________ on board with self-igniting light? (A) there exist (B) there is (C) there are (D) are there

4. Stand by on VHF channel 13 until the pilot transfer completed. (A) Watch on VHF CH 13 until pilot transfer begins. (B) Watch on VHF CH 13 during the period of pilot transfer. (C) Do not use VHF CH 13 before pilot transfer is completed. (D) Afet pilot transfer is completed, you should stand by on VHF CH 13.