世足

世 = 廿 + L : Mnemonic symbol: the WTO or WHO.

Sherlock Holmes (sh) is cleaning a flower pot (廿) under the shower of the space station's bathroom (Ø4) with a loofah (L) because he didn't quite understand a poster next to the shower from the WHO (世) explaining dangers arising from different germs.

In this case, L is for loofah.

足 = 龰 + 口 : Mnemonic symbol: a football. Zapatista Zebra (zu) wants to pimp his football (足) in the space station's kitchen (Ø2). He thinks that a few more vitamins wouldn't hurt, so he extracts the vitamins from a mandarin (口) with a syringe (龰) to inject them into his football.