One week, a construction worker bought \( 40 \frac{1}{10} \) pounds of nails. The next week, he bought \( 2 \frac{1}{2} \) times as many nails as the week before. How many pounds of nails did he buy the second week? \[ \begin{array}{ll}\text { A } 16 \frac{1}{25} \mathrm{lb} \\ \text { B } 99 \frac{1}{4} \mathrm{lb} \\ \text { C } 80 \frac{1}{20} \mathrm{lb} \\ \text { D } 100 \frac{1}{4} \mathrm{lb}\end{array} \]

10 misol \( 25786 \cdot 37+24!\cdot(45980+12890)+(45) \) \( 793 \cdot 23451 \cdot 24 \)

\begin{tabular}{|l|l|}\hline 7 & Luas permukaan bola adalah \\ \( 803,84 \mathrm{~cm}^{2} \). Hitunglah volume bola \\ tersebut dengan \( (\pi=3,14)! \)\end{tabular}

\( \frac{a^{a} \cdot a^{3} \cdot a^{2} \cdot 2 \cdot a^{-1}}{\left(a^{6}: a^{1}\right) \cdot a}= \) b) \( \left(\frac{m \cdot m^{3}}{r^{3}}\right)^{4} \cdot\left(\frac{m^{5} \cdot m^{-2}}{r^{9}}\right)^{4} \) c) \( \sqrt[3]{\frac{x^{9}}{y}} \) \( (\sqrt{\sqrt[3]{0,5}})^{6} \cdot\left(\frac{9}{5}\right)^{-1}= \)

Encuentre un sistema lineal \( 4 \times 4 \) cuya solución sea \[ \left(\begin{array}{l}1 \\ 2 \\ 3 \\ 4\end{array}\right)+s\left(\begin{array}{l}4 \\ 5 \\ 6 \\ 7\end{array}\right)+t\left(\begin{array}{l}7 \\ 3 \\ 2 \\ 1\end{array}\right), \quad s, t \in \mathbb{R} . \]

Compare the absolut a. -4.5 and 3.75