Dear Sirs

First of all, I am stunned at the response.

Now I understand the formula well.

I thank Mr. Edd Slater for being an opening bats man. I liked his
simplistic explanation.
I thank Mr. Robert Nichols for the comments on formula of my
understanding.
I thank Mr. Spehro Pefhany for a in-depth explanation with calculus.
My hearthy thanks.
I enjoyed out -of-square answers of M/s Doug Goncz, Gunluvver2, Errol
Groff, Robin S, .Michael

My special thanks for Google.

Bye

N. Ayyavu


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