9.7300x10^2
+
9.8700x10^3

[?]x10^[?]

1.0843×10^4

Explanation:

If we are to add 9.7300x10^2 + 9.8700x10^3, we must first make the powers of the both to be be the same so that we can carry out any mathematical manipulation of interest. So we can have;

9.7300x10^2 + 98.700x10^2

When we now add the both we have (9.7300 + 98.700)×10^2.

This now gives us the result, 108.43×10^2 which is correctly written as 1.0843×10^4, according to the rules of writing in scientific notation.

m=9

step-by-step explanation:

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.