c. Write \( \sqrt[3]{81} \) in the simplest form or as \( \sqrt[n]{b} \). \( \sqrt[3]{81}=\square \) (Simplify your answer. Type an exact answer, using radicals as neede example Get more help

10. I en skål med 200 vindruvor är \( 90 \% \) gröna och resten blåa. Rickard äter enbart gröna vindruvor. Hur många vindruvor har Rickard ätit när andelen gröna vindruvor har minskat till \( 80 \% \) ?

2. \( \frac{1}{\sqrt{3}+\sqrt{2}} \div \frac{1}{\sqrt{4}+\sqrt{3}} \div \frac{1}{\sqrt{5}+\sqrt{4}}= \) ?

Simplify the expression without using a calculator. \( \ln e^{2}=\square \)

Find \( \|\mathbf{v}\| \). \( \mathbf{v}=-3 \mathbf{i}+7 \mathbf{j} \) \( \begin{array}{l}\|\mathbf{v}\|=\square \\ \text { (Simplify your answer. Type an exact answer, using radicals as needed.) }\end{array} \)

Simplify the expression without using a calculator. \( \log _{9} 9=\square \)