Solve the following and express each answer in scientific notation and to the correct number of significant figures. a). (5.3 x 10^4) + (1.3 x 10^4) b). (7.2 x 10^-4) /(1.8 x 10^3 c). 10^4 x 10^-3 x 10^6 d). (9.12 x 10^-1) - (4.7 x10^-2 e). (5.4 x 10^4) x (3.5 x 10^9)

The answer to the correct number of significant figures is as follows:

A). (5.3 x 10⁴) + (1.3 x 10⁴)=6.6 x 10⁴

B). (7.2 x 10⁻⁴) /(1.8 x 10³)=4×10⁻⁷

C). 10⁴x 10⁻³ x 10⁶ =10⁷

D). (9.12 x 10⁻¹) - (4.7 x10⁻²)=8.65×10⁻¹

E). (5.4 x 10⁴) x (3.5 x 10⁹)=18.9×10¹³

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