0. The current water level of a swimming pool in Arizona is 6 feet. The rate of evaporation is \( 1 / 3 \) foot per week. Find out how much water is left after 7 weeks.

Ejercicio 2: Cinco carpinteros necesitan 21 días para entarimar un suelo. ¿Cuántos carpinteros seran necesarios si se desea hacer el trabajo en 15 dias?

11. If the average (arithmetic mean) of five numbers is 4 and if four of the numbers are \( 1,3,5 \), and 7 , what is the fifth number? \( \begin{array}{llll}\text { (A) }-1 & \text { (B) } 0 & \text { (C) } & \text { (D) } 6\end{array} \) (E) 9 \( \$ \begin{array}{l}\text { (D) }\end{array} \)

3.1. Simplify each of the following ratios: 3.1.1. \( 4: 28: 16 \) 3.1.2. \( 6: 1.25: 2.5 \) 3.1.3. \( 3.6: 27: 13.5 \) 3.2. Distribute \( R 24000.00 \) in the ratio 2:1:5.

Ex. 3 Simplify \( \left(9.6 \times 3.6 \div 7.2+10.8\right. \) of \( \left.\frac{1}{18}-\frac{1}{10}\right) \)

What is 100 degrees Celsius equal to in Fahrenheit?