Bill Nye introduces reptiles and explains how they are able to live in different environments around the world by regulating their own body temperature. As cold-blooded organisms, they don't keep the same body temperature throughout the day.
Kramer gets a new hot tub and enjoys relaxing in it. While sleeping in the hot tub, his heat pump breaks, and the temperature gradually decreases from over 100 degrees Farenheit to about 58 degrees Farenheit. He meets up with Jerry and George in the coffee shop wearing multiple layers of clothes.
Forrest gets invited to meet President John F. Kennedy at the White House because he's an All-American football player. He describes the perks of the event and drinks a lot of Dr. Pepper. When it's his turn to meet the President, he says that he has to pee.