國史

国 = 囗 + 玉 : Mnemonic symbol: a nation's flag. Let's say the Chinese flag.

In the observatory's kitchen (o2) Gitta Giraffe (gu) is practising her ballet performance. She got a whole crate (囗) full of jade bracelets (玉) and flags (国) and fixed one flag to each jade bracelet. This makes a perfect combination for throwing the ring with the flag waving behind it and catching the ring again after a few pirouettes.

史 = 口 + 乂 : For a mission in the space station (Ø3) Sherlock Holmes (sh) has to find out the history (史) of a mandarin (口), so with a pair of pliers (乂) he took to the space station he squeezes the mandarin like an orange.