水锤波的传播速度与管壁材料、管壁厚度、管道直径及水的弹性模量有关，其中与管壁材料特性的关系最为密切
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An administrator needs to be able to list the number and size of backup sets on a tape. Which of the following procedures accomplish this（）
A. Use the tcopy /dev/rmtl until an end-of-tape error notification is received.
B. Use the cpio -idmv < /dev/rmtl until an end-of-tape error notification is received.
C. Use the tar -tvf /dev/rmtl repeatedly until an end-of-tape error notification is received.
D. Use the dd if=/dev/rmt0.1 bs=128k count=EOT until an end-of-tape error notification is received.
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