During a reaction, age for reactants is -750 KJ/mole and age for products 920 KJ/mole which statement is correct about the reaction correctly compares energy in bonds

Large helium-filled balloons are used to lift scientific equipment to high altitudes. what is the pressure inside such a balloon if it starts out at sea level with a temperature of 10.0ºc and rises to an altitude where its volume is twenty times the original volume and its temperature is – 50.0ºc ?