因變量

因 = 囗 + 大 : Mnemonic symbol: the close reasoner René Descartes.

因 = 囗 + 大 : In front of the encampment ((e)n1), René Descartes (因), Maud Younger (y) and a robot (大) are starting a big rave. The robot sits inside a big box (囗) and is the master of ceremony, while René and Maud are dancing on the square. They started this rave to collect money for a good cause (因).

变 = 亦 + 又 : In anthill's bathroom the also-ran is sparring with Brunhilde. In her mind she imagines changing into a boxing grizzly bear.

变 = 亦 + 又 : I think 变 does look like a grizzly bear with a beret. 又 is the snout, and the two eyes are the two strokes of 八.

量 = 旦 + 里 : Li Qingzhao (li) uses a measuring cup (量) for a recipe in the anglepod's kitchen (ang2). Unfortunately she made a terrible mistake: instead of measuring cups (旦) of sunflowers (里), she throws sunflowers and cups together into a measuring cup.