A sonic boom is like every sound in that it is ______.
A.explosive
B.caused by compressed tar
C.a pressure disturbance
D.shock wave
An appropriate title for this passage would be ______.
A.The Sonic Boom
B.Air and Its Effects
C.Faster Than Sound
D.Problems Facing Aviation Today
A.认监委发布的《绿色建材产品分级认证实施通则》(CNCA-OGP-13:2020)
B.认证机构自行制定的相应的认证实施细则
C.相应的绿色建材产品标准
D.相应的产品标准
A.特级
B.四级
C.五级
D.六级
A.管控措施
B.排查内容
C.排查标准
D.排查方法
A.设备设施
B.排查内容
C.排查标准
D.作业活动