and i'm just kidding around and going like this, "humba, humba, humba, snow, snow, snow." and someone says, "hewitt, you're taking yourself too seriously." and all of a sudden-- "hewitt, son of a gun, i underestimated you, man." and the snow is all-- how did i know it's gonna snow? the same type thing, that room got-- i mean, not room-- that air got noticeably warmer. so in changes of state, you get an energy transfer. and i think we have a diagram in the book that looks something like this. okay, you go from the solid to liquid. does it take energy to make it go from solid to liquid or give up energy? let's suppose this substance is h2o. it's an easy one to remember. ice, water, steam. you go from ice to water, it's gonna have to take in energy, right? you'll have to put energy into the h2o. and if you wanna turn liquid to gas, say, water to steam, you gotta keep putting the fire in, yeah? so you get energy in going this way. but how about the converse? that's the part we're talking about now. how about you go from a gas to a liquid? does the gas give up energy or take it