are those seeds likely to become more digestible?
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DifficultNo throwing, so a sling is outNo elastic, ruling out a number of catapult designsNot much in the way of structural materials, so a trebuchet would be a challenge to makeIf the rubber stopper will fit nicely in the straw, then how about an air cannonConstruct an air chamber or bellows using the foil along with whatever other components you desire, with a straw for a barrel attached to itDon't forget to keep something to use as a ramrod for loading! Fire by hitting the air chamberDurability may be a problemIf airtime or distance are the criterion for judging, then do consider designs that involve putting the stopper on a gliderIf you want something really ersatz, make a hot-air balloon using the foil for the envelope, and the string and pipe cleaners for fuelDon't fly it indoors!
If you got a blender, you can also ground flax seeds sprinkle it in food drinks.
