Combining scripts/functions to get CPU usage, memory usage and free disk space

Could you help me combine these three scripts to a format that's like this

   

ComputerName     CPUUsageAverage    MemoryUsage    C PercentFree
xxx                                                  12            50%              30%

 The way I execute this is:

Get-content '.\servers.txt' | Get-CPUusageAverage

Here are the scripts:

CPU

 

  Function Get-CPUusageAverage    {    $input|Foreach-Object{Get-WmiObject -computername $_ win32_processor | Measure-Object -property LoadPercentage -Average | Select Average}    }

Memory

       

Function get-MemoryUsage    {    $input|Foreach-Object{    gwmi -Class win32_operatingsystem -computername $_ |    Select-Object @{Name = "MemoryUsage"; Expression = { “{0:N2}” -f ((($_.TotalVisibleMemorySize - $_.FreePhysicalMemory)*100)/ $_.TotalVisibleMemorySize) }
    }    }    }

C PercentFree

 

  Function get-CPercentFree    {    $input|ForEach-Object{      Get-WmiObject -Class win32_Volume -ComputerName $_ -Filter "DriveLetter = 'C:'" |      Select-object @{Name = "C PercentFree"; Expression = { “{0:N2}” -f (($_.FreeSpace / $_.Capacity)*100) } }
     }      }