please answer in detail thx

5. A. Using the mass balance principle, derive the equation that describes the change in gaseous concentrations over time inside a static chamber, use a sketch. (KB.2 2 points) (10 min) B. If the source enclosed by the chamber is emitting at a rate of 39,000 mg CH /hour, the initial concentration of CH, in the chamber is 202 ppm, and the chamber volume is 1,460 L, at what time will the concentration of CH in the chamber reach explosive levels of (100% LEL). Note: 1% LEL = 500 ppm * Where P= 1 atm; R = 0.0821 ; T = 295 K