Sink or Bob - will it bob in the apple-bobbing tub?

Line up 2 to 8 everyday things for an apple-bobbing tub, call each one bob or sink, and pick plain or strong salt water. Free in the browser: a galvanised tub drawing, the page's own table of rough densities (estimates) for about 50 common things, a fixed float rule, a score of your calls and SVG and PNG downloads. One metered task takes each item back to first principles - the hunch it tests, two basic facts about what it is made of, a density range and a verdict (bobs, rides low, sinks or depends) - plus a safe home check and a tally; the page re-checks every verdict against the run's own numbers. Living things and hazardous items are declined. Built on @danielmiessler/firstprinciples.