SortStack #14 — 2026-06-23

By weight · Order from lightest to heaviest.

1. An average adult domestic cat 4.2 kg

   Cats purr at frequencies between 25 and 150 Hz — a range some studies suggest can promote bone and tissue healing.

2. An adult red fox 5.2 kg

   Red foxes may use Earth's magnetic field to aim their famous pouncing dives — they prefer striking toward the northeast.

3. A full backyard barbecue propane tank 17 kg

   The familiar grill tank stores propane as a liquid; on a hot summer day the pressure inside can roughly triple.

4. A Holstein dairy cow 680 kg

   A productive dairy cow gives about 30 liters of milk a day — and burps enough methane to matter in climate accounting.

5. An M1 Abrams main battle tank 62 t

   Despite the bulk it tops 65 km/h, powered by a jet-style gas turbine engine that can run on almost any fuel.

6. The London Eye observation wheel 2.1K t

   It was meant to stand for just five years when it opened in 2000; instead it became the UK's most popular paid attraction.

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