Omega and theta you have a value, up value; this is like that how to find out that value, that is found out by taking S 2 D into omega multiply f into theta. So, for that given omega you know H 2 D that, that is actually the bell curve that original bell curve. But multiply that by an f theta; that means, you you are lowering it down actually see f theta will be actually a function which will obviously, become as theta goes to 90 degree becomes 0. So, it just a number, so you are just as if you are pulling this down as if this graph is pull down as you are spreading it.