某机构要对青少年网瘾行为进行研究,研究者从几个适合的调查对象开始,然后通过他们得到更多的调查对象,一步步扩大样本范围。这种抽样方法称为()。
A. 偶遇抽样
B. 配额抽样
C. 简单随机抽样
D. 滚雪球抽样
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患者,男性,39岁。因车祸发生脾破裂,急诊入院。T36.4℃,BP70/50mmHg,P100/min,R24/min,患者口渴,烦躁不安,皮肤苍白,四肢湿冷。该患者的表现提示其处于()
A. 休克代偿期
B. 休克早期
C. 休克失代偿期
DIC
E. 多器官功能受损
下列()项情形导致合同无效或被撤销、解除的,买受人可以请求返还已付购房款及利息、赔偿损失,并可以请求出卖人承担不超过已付购房款一倍的赔偿责任。
A. 故意隐瞒所售房屋已经出租的事实
B. 进行所售房屋为学区房的虚假宣传
C. 故意隐瞒所售房屋已经抵押的事实
A log logical volume is created as indicated below: root@host1:/# mklv -a c -t jfs2log -b y datavg 1 loglv00 root@host1:/# lsvg -l datavg datavg: LV NAMETYPELPsPPsPVsLV STATEMOUNT POINT loglv00jfs2log111closed/syncdN/A A new filesytem is then created using the new log logical volume.When the administrator attempts to mount the filesytem, the following error occurs: root@host1:/# mount /newfs mount: 0506-324 Cannot mount /dev/lv00 on /newfs: A system call received a parameter that is not valid. Which of the following actions will resolve this error?()
A. Recreate the file system with -p rw flags and re-mount.
B. Run ‘logform /dev/loglv00’ and hit ‘y’ to destroy all data.
C. Run ‘clrginfo -p’ to clear the invalid filesystem parameter.
D. Change ‘account = true’ value in /etc/filesystem to ‘account = false’.