 Okay, so this one, we're going to do the shortcut of taking the Rieberg energy equation and just figuring out what the energy of the transition is, instead of taking it using the Rieberg wavelength equation and then putting that into the various other equations then getting your energy out through that, okay, so we're going to show a shortcut of how to do this. So it's very similar to the Rieberg equation, so it's energy instead of 1 over wavelength equals RE and that's the Rieberg energy constant, which I've written down for you up here, times 1 and 2 squared minus 1 over... so that's what's going on here, it said that the transition was from n equals 5 to n equals 2, right, so in R3. In this case, n equals 5 is 1 and n equals 3 is 2. So let's just go ahead and plug those in. Let's plug everything in. Notice the negative sign here, okay, so what is that saying is that this transition, well, we'll see in a second. And again, these are exact numbers, so there's no real significant digits here, so in this problem you can put for a final answer whatever it felt like. And since I don't have much room on this board, I'm just going to erase these and put 9 and 20. Okay, so this is what I was referring to earlier when I kind of stopped. This number is bigger than this number, is everybody clear on that, right? So since that's the case, we're going to get a positive number here. Does that make sense? Since we're subtracting, we're having a bigger number and subtracting a smaller number from it, does that make sense? So the overall answer is going to be negative. Does that make sense? Because this is some negative times a positive. And this is what I was saying, since we have this transition going from a higher energy to a lower energy, we would expect to lose energy. Okay, so let's just do this. And this is the energy of one photon, so you would expect this to be a tiny number, not to mention that. We've already got a small number there, so I got a negative 1.5, 5, and just turn to the negative 19. That's how much energy it takes to make this transition from energy level 5 to energy levels. Does that make sense? We'll do, let's do another one. Let's do kind of a follow-up question where we go from, and I know probably you guys will figure out what the difference will be without doing it, but let's do one going from energy level 3 to energy level 5. Okay, I think that... So what happens? It was released as like a photon of light or some other type of radiation, like thermal radiation or something like that. So you have to, it's like that conservation of energy, law of conservation of energy, you have to, there has to be a constant amount of energy, you know, in the system and surrounding. So, yeah, you're releasing it as, that's what I kind of wanted to say here. I was going to say HD, but I don't know if it's actually visible light or something like that. So, or we could say it's thermal energy, so energy in general, better kind of connotation, if that makes sense. But it's a good question. Is that good? Can we kill this one?