地质学

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.

质 = ⺁ + 十 + 贝 : James II of England (zh) captured a crab (贝) and keeps it as a hostage (质) In the space station's bathroom (Ø4). James II of England wants to find out more about the nature (质) of the banana tree (⺁), so all the crab gets to eat is the banana trees. Secretly the crab set up a small cross (十) to which it prays everyday for its release.

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.