Basic Linux Management Commands

$17.$ What command would you use to determine the version of linux you are running, the kernel version and if your are running a $32$ or $64$ bit processor $($use google$)$

$18.$ What command can you use to determine used and free hard disk space $($ include the appropriate option to ensure disk size is in human readable format $)($ use google $)$

$19.$ What command will display the disk usage of the files in your $/$home$/-F$