工作风缸充气止回阀在制动减压时，能防止工作风缸内的压力空气向（）逆流，以避免产生不制动或制动力不成比例的现象。 列车管。 制动管。 总风管。 撒砂管。
During reboot the system hangs with an LED 0554 message that means， "The boot device could not be opened or a read failed." What recovery procedures should be taken？（） Boot in maintenance and use fsck to check hd5.。 Boot in maintenance mode， access the rootvg and check the /etc/inittab for corruption.。 Boot in maintenance mode， access the rootvg and rebuild the boot image using the bosboot command.。 Boot in maintenance mode， access the rootvg and use the bootlist command to create a valid boot list.。
（）是加强素质教育，提高体育教学质量，增进学生健康的物质保证。
测定受检血浆中有否肝素或类肝素物质存在，常用的试验是（） 蕲蛇酶时间测定。 蝰蛇毒试验。 甲苯胺蓝纠正试验。 凝血酶原纠正试验。
Examine the following ALTER command： SQL> ALTER DISKGROUP dgroup1 UNDROP DISKS； What is the purpose of the command？（） It cancels all pending disk drops within the disk group.。 It restores disks that are being dropped as the result of a DROP DISKGROUP operation。 It mounts disks in the disk group for which the drop-disk operation has already been co pleted。 It restores all the dropped disks in the disk group for which the drop-disk operation has already been completed。 It adds previously dropped disks back into the disk grou。
有一宗房地产，评估基准日后第一年的纯收益预计为70万元，资本化率为8%，以后未来各年的纯收益将在上一年的基础上增长1%，则该宗房地产的在永续使用的前提下评估价值最近近于（）。
