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Two scientists use a massive, illuminated periodic table of elements as they discuss the element holmium in the Lawrence Hall of Science at the University of California, Berkeley. (Photo by ?? Ted Streshinsky/CORBIS/Corbis via Getty Images)

How many elements of the periodic table could we safely get rid of?

There are only a few elements essential to biology and modern technology, say our readers

Close-up view of Black hole with Earth planet in deep space. Realistic science fiction art. Elements of this image furnished by NASA.; Shutterstock ID 2169109081; purchase_order: -; job: -; client: -; other:

If nothing can escape a black hole, how come gravity seems to?

High five from a cute scruffy dog with a big smile! Cream wall background, shallow depth of field. Clever dog, the Bailey lightbox

Does left- and right-handedness exist in animals?

Close up photo of peony flower bud with water drops at sunlight after rain in garden. Natural floral background. Gardening, spring season, growth concept.; Shutterstock ID 1726658389; purchase_order: -; job: -; client: -; other:

This week鈥檚 new questions

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Is an AI version of Mark Zuckerberg 鈥� or any boss 鈥� a good plan?

Is there an equivalent of being ambidextrous for feet?

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Striking photo essay examines deadly spread of dengue fever in Nepal

Twisteddoodles on the far side of the moon

Tom Gauld on the Artemis II mission

Why do people scrunch up their eyes to see more clearly? Part 2

Why do people scrunch up their eyes when they want to see more clearly? It seems to be counterintuitive. (continued)

This week鈥檚 new questions

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How many dachshunds would it take to get to the moon?

Twisteddoodles uses Gen Z slang to explain chemistry

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Why cloning anyone 鈥� even Jim Carrey 鈥� isn’t the best plan ever