DRAG DROP
You have a server named Server1 that runs Windows Server 2012 R2.
You need to perform the following storage configuration tasks on Server1:
• Bring a disk named Disk1 online.
• Defragment a volume named Volume1.
• Remove a disk named Disk2 from a storage pool named Pool1.
Which cmdlet should you use to perform each task?
To answer, drag the appropriate cmdlets to the correct tasks. Each cmdlet may be used
once, more than once, or not at all. You may need to drag the split bar between panes or
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Answer: 
Explanation:
I think the correct order would:
Bring a Disk: Initialize-disk
Defrag: Optimize-Volume
Remove a Disk: Remove-PhysicalDisk
No, you have to use set-disk to bring a disk online: http://technet.microsoft.com/en-us/library/hh848649.aspx
From :https://technet.microsoft.com/en-us/library/hh848649.aspx
This example takes a disk that is offline and makes it online.
Windows PowerShell
PS C:\> Set-Disk -Number 5 -IsOffline $False
Why not Initialize-Disk?
From: https://technet.microsoft.com/en-us/library/hh848708.aspx
Initialize-Disk: Initializes a RAW disk for first time use, enabling the disk to be formatted and used to store data.
set-disk just bring the disk online but partition remain RAW
initialize-disk will bring disk online and partition it in either MBR or GPT
set-disk will do just what the question and no more.
initialize-disk may cause the disk not usable for some applications
https://technet.microsoft.com/en-us/library/hh848649(v=wps.630).aspx
https://technet.microsoft.com/en-us/library/hh848675(v=wps.630).aspx
https://technet.microsoft.com/en-us/library/hh848697(v=wps.630).aspx