This week’s new questions

What could happen to change gravity on Earth as we know it?

Kurt Schwalbe (age 7), Whitley Bay, Tyne and Wear, UK

San Francisco sourdough bread tastes completely different to sourdough from the UK. Are UK yeasts different from Californian ones or is this due to the bread-making process?

Pamela Radford, Horsforth, Leeds, UK

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