C

Using the formula for factoring \( a^3-b^3 \) to rationalize the denominator of \( \frac2{\sqrt[3]{25}+\sqrt[3]{15}+\sqrt[3]{9}} \) you get:

After rationalizing the denominator \( \frac{\sqrt{\sqrt{13}+\sqrt{12}}}{\sqrt{\sqrt{13}-\sqrt{12}}} \) we get:

The number \( \sqrt[5]9 \) is bigger than:

The approximate value of the number \( 1.3\cdot10^{-0.4} \) is \( 0.5175393 \). What is the approximate value of the number \( 39\cdot10^{0.6} \)? Give your answer to three decimal places. Do not use a calculator.