Smart Aleck

There was this smart aleck who sent the following e-mail to his dad from his college in the US:

Dear Dad,

I am making lot$ of friend$ and $tudying like nobody'$ bu$ine$$ and I am $imply $o happy $ince I came to the U$. $end my love and ki$$e$ to mum and my baby $i$ter.

Love,
Your $on

The dad replies as follows:

Dear Son,


I kNOw that astroNOmy, ecoNOmics, and oceaNOgraphy are eNOugh to keep an hoNOur's student busy. Do NOt forget the pursuit of kNOwledge is a NOble task.

Love,
Your Dad