Design an experiment that demonstrates that algae release oxygen when exposed to light

Experience. Algae release oxygen in the light.
Take a glass filled with water.
We place the shoot of the aquatic plant Elodea in the water with a cut upwards, cover it with a funnel, on which we put a test tube.
Now we put the glass in a bright light.
In the light, in a glass, Elodea emits gas bubbles.
We carefully remove the test tube filled with gas, closing its hole with your finger.
Let’s put a smoldering torch into the test tubes. It lights up with a bright flame.
This means that oxygen has appeared in this test tube (only this gas supports combustion).

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