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how to do the cos-1 in the calculator ?? help me please!

What is the volume of a cone with a radius of 4.7 units and a height of 9.2 units? Use 3.14 for pi and round to the nearest hundredth.

$\begin{array}{rcll} V &=& \frac13 \cdot \pi r^2 \cdot h \\ V &=& \frac13 \cdot 3.14\cdot (4.7)^2 \cdot 9.2 \\ V &=& \frac13 \cdot 3.14\cdot 22.09 \cdot 9.2 \\ V &=& \frac13 \cdot 638.13592\\ V &=& 212.712 \end{array}$