How to click on the select_list little drop down arrow

[Vikash Kumar]

I am using Watir and ruby.

I have a web page in which there is a select list. I want to click on
the drop down arrow on it, so that entire option in it get visible.
Then we can choose some particular option from it.

I am using

require 'watir'
instance = 'http://localhost/index.asp'
ie=Watir::IE.start(instance)

#If we use ie.select_listname, "rate").select("Hi") then it get
selected but I want to click on the arrow, then after choose option from
it.