地球科学

地 = 也 + 土 : Dorothy Gale (di) hates the cleanliness of the space station, so she used an excavator (也) in the space station's bathroom (Ø4) to dig a pile of dirt (土) out of the ground (地) for a mud bath.

球 = 求 + 王 : Martin Luther King and the Queen of Hearts are playing with a globe beach ball in the outhouse's kitchen. They put a service request bell just between them and bounce their beach ball off of it with a loud "DING".

科 = 斗 + 禾 : In front of the elevator, Karl Marx wants to conduct one of his science experiments. He wants to condition the matador to only eat cereals until the end of his life.

学 = 小 + 冖 + 子 : Xu Xian wants to study scienceology and learn more about daisies. Just inside the elevator's kitchen, he put some daisies into a prize cup and covered them with a cooking top. He wants to study the growth rate of the daisies depending on the pH of the water in the prize cup.