Thanks; I will chew on that for a while, and will ask again if I remain stumped. I don't have any graph paper handy, so this'll be computer or nothing...
At least it's blindingly obvious which bulb has to be last. :-)
The beam passes through the previously mentioned refractor twice. There's a single mirror somewhere directly left, and somewhere directly right of that refractor.
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bulb that the beam passes through.
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At least it's blindingly obvious which bulb has to be last. :-)
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paper handy, so this'll be computer or nothing...
I just used a computer myself.
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a single mirror somewhere directly left, and somewhere directly right of that
refractor.
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Phew. Finally. Thanks.
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