Everyone is acquainted with paper milk cartons, I think.
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At the top at one end, under the pitched "roof" it says "To Open" with arrows to the left and right that say Push up Here.
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When I was in high school, I would push where it said Push, the middle would split at the ridge, and I would go to the newly opened seam and22) pull down what was the lower layer, now the outer layer, and voila, I had a spout with which to pour out the milk, even directly into my mouth.
But about 10 years later step 22 above became very hard. The layers were glued together and I coudln't separate them. I had to use a knife!
I was patient in my 20's and I figured they would fix this, get it back the way it was.
Now it's 50 years later and they still don't work right. Why is that?
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the video, where an Austrian official demonstrateg how to use their newly-introduced wax/cardboard milk carton.
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same video, different comments.