Scientific notation consists in writing the result of a measurement as a product with two parts: a number between 1 and 10 and a power of 10. The number is represented with a whole number followed by all the significant figures and multiplied by the power of 10. The power of 10 is called the exponent.
You can practise as much as you like in the following visual; you just have to click on init and a different exercise will appear.

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