structural

I am not sure that many structurals will try to give you an answer directly on what you have, what is the specific shape (there are many) of your beam, i.e.: I-beam or T-beam the load depends on how you mount the ends of the beam as well, there is not enough here to give you an answer, but it is a simple statics type of homework or test problem for a 3rd year college statics and dynamics class. I suggest you look in the book store or library for a statis book for your structure load, and deteriment the moment of Inertia and modulas for your beam then you can plug and chug. (and do not neglect the uniform dead load of the beam itself...)

Thank you for your response.