So you want the unknown on one side and the knowns on the other side. And this is what we get. So what we do is we find the common denominator here, multiply this by Ti and this by TF, bring everything over, bring the R over, and then bring the negative over, and we get this. Finally, we plug in all our information. So our R, it's 8.31
joules per mole times Kelvin, times natural log of 360 or 40, which is simply nine times. Now, we have to use our temperature in Kelvin, and that means we have to convert from celebrates to Kelvin by simply adding 273 to each temperature.