Riddles 03

The Riddler

No 1.  I sound like one letter but I'm written with three.

I show you things when you look through me.

What am I?

 

No 2.  In a clothing store in Rowayton USA, 

socks cost 25 dollars,

a vest cost 20 dollars

a blouse cost 30 dollars

a tie cost 15 dollars

with this method, how much does underwear cost?

 

Bring it on Riddler