单项选择题
Changing rescuers while carrying out artificial respiration should be done（）.
A.without losing the rhythm of respiration B.only with the help of two other people C.by not stopping the respiration for more than 5 minutes D.at ten-minute intervals
单项选择题 An uncontrolled flow of gas，oil，or other well fluids into the atmosphere is called a（）.
单项选择题 All the traces are（）old ones.
单项选择题 A VESSEL，OTHER THAN A RESCUE UNIT，DESIGNATED TO CO-ORDINATE SURFACE SEARCH AND RESCUE OPERATION WITHIN A SPECIFIED AREA is known as（）.
