This week’s new questions

What caused the contrails in the sky to end so abruptly (see picture)? And what is the optimal number of piercings to make in the film covering a microwave meal?

20 July 2022

This photograph is of the sky over north London on Wednesday 15th June at 8:13 am. The picture Is cropped to centre the image. The effect was not due to camera or glass of vehicle photo was taken from and looked identical to naked eye. What can have caused the contrails to end so evenly? No aircraft were immediately apparent, it did turn out to be a remarkable hot day. I am assuming my passenger?s suggestion of a glitch in the matrix leading to an incomplete sky rendering is incorrect- can you or your readers provide a more sensible explanation — Rob Allwright

Broken clouds The image is of the morning sky over London one hot day in June. Why do the contrails end so evenly and abruptly?

Rob Allwright, Bushey, Hertfordshire, UK

Woman Putting TV Dinner Into Microwave Oven To Cook; Shutterstock ID 234670651; purchase_order: -; job: -; client: -; other: - — Shutterstock/Monkey Business Images

Hole number My microwave meal says remove sleeve and pierce film. What is the optimal number of holes I should make?

Bob Yelland, Alton, Hampshire, UK

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