The expression in scientific notation is given as follows:
3.5 x 10³.
<h3>What is scientific notation?</h3>A number in scientific notation is given by:
With the base being .
For this problem, the expression is given by:
When two factors of a multiplication have the same base and different exponent, we <u>keep the base and add the exponents,</u> hence:
5 x 4.2 = 21, hence the expression is:
When we divide two terms with the same base and different exponents, we keep the base and subtract the exponents, hence:
Which is the simplified expression.
More can be learned about scientific notation at brainly.com/question/16394306
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