sort from the smallest number to the highest number

From: Boon Chong Ang (BCANG_at_altera.com)
Date: 01/30/04 

Date: Fri, 30 Jan 2004 13:17:38 +0800
To: "Hanson, Rob" <rhanson@aptegrity.com>, <beginners@perl.org>

Hi
Just say I want to sort the row by using the fifth column data as reference from the smallest the largest number, if using sort,
It will give me result like this

Abc 12.8 8 "left" 1 1.7
Def 13.8 9 "top" 0 19.7
gef 14.8 9 "left" 0 19.7
Dgf 12.3 9 "right" 4 2.6
bac 12.8 8 "left" 1 3.7
etg 12.8 2 "left" 7 34.7
efg 16.8 5 "right" 0 56.7
baf 32.8 7 "bottom" 5 79.8
cef 16.8 4 "right" 0 89.7

but what I want is like this, what so I do to achieve this effect?

Abc 12.8 8 "left" 1 1.7
Dgf 12.3 9 "right" 4 2.6
bac 12.8 8 "left" 1 3.7
Def 13.8 9 "top" 0 19.7
gef 14.8 9 "left" 0 19.7
etg 12.8 2 "left" 7 34.7
efg 16.8 5 "right" 0 56.7
baf 32.8 7 "bottom" 5 79.8
cef 16.8 4 "right" 0 89.7

Thank you & best regards,
ABC