Ideal Gas Law Question....please help?

A particular balloon can be stretched to a maximum surface area of 1257 . The balloon is filled with 3.2 of helium gas at a pressure of 765 and a temperature of 305 . The balloon is then allowed to rise in the atmosphere. ume an atmospheric temperature of 273 and determine at what pressure the balloon will burst. (ume the balloon to be in the shape of a sphere.)