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Answer:
9.32×10⁻³
Explanation:
Scientific notation is the way to express the large value in short form.
The number in scientific notation have two parts.
. The digits (decimal point will place after first digit)
× 10 ( the power which put the decimal point where it should be)
How to add the number in scientific notation with same exponent.
7.21 ×10⁻³ + 2.11 ×10⁻³
exponent of both values are same thus we will take it common.
[7.21 + 2.11 ]×10⁻³
9.32×10⁻³