Suresh,
You may find it useful to download the MIDUSS Reference manual at no
cost from the site below
<http://www.miduss.com/resources.htm#MIDUSS%20manual> .
Chapter 8 covers the relevant theory on some of your questions. In
particular you need to be careful in the use of empirical
coefficients that are often dependant on the system of units employed.

For solutions to actual problems you may download a demonstration
copy of the MIDUSS program that has many features to assist in
reservoir (Pond) routing. You can use the available hydrology
commands to generate the inflow hydrograph although in the
demonstration version some restrictions apply. Alternatively you can
prepare an ASCII file defining the hydrograph and import this to the
program. The MIDUSS program can be downloaded at
<http://www.miduss.com/MIDUSS_v2_downloads_user_select.htm>.

Good luck
Alan A. Smith