HELP MEE PLZ I DON'T UNDERSTAND THIS

Choice D.  

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Work Shown:

We multiply the coefficients 9.2 and 7 to get 64.4, which is the same as 6.44*10^1 in scientific notation. When multiplying exponential expressions with the same base, we add the exponents

This is what the steps could look like

The final result is in scientific notation as the coefficient c is restricted such that

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have