19. La distancia de frenado de un auto en ciertas condiciones es directamente proporcionalidad a la velocidad del auto. Si la distancia de frenado de un auto que conduce a \( 40 \mathrm{~km} / \mathrm{h} \) es de 50 metros, ¿cuấ sería su distancia de frenado si conduce a \( 100 \mathrm{~km} / \mathrm{h} \) ? A) 20 metros B) 75 metros C) 125 metros D) 150 metros

Consider the following function. \[ f(x)=1-x^{2 / 3} \] Find \( f(-1) \) and \( f(1) \) \( f(-1)=\square \) \( f(1)=\square \)

The retail flat rate in dollars for first-class mail weighing up to 5 ounces could be computed by the piecewise-constant function \( f \), where \( x \) is the number of ounces. (a) Evaluate \( f(1.1) \) and \( f(4) \). Interpret your results. (b) Sketch a graph of \( f \). What is the domain of \( f \) ? What is the range of \( f \) ?

1a. Calculate the next two terins of each of the following sequences \( \begin{array}{ll}\text { (a) } 11,8,5, \ldots & \text { (d) } 4,9,14, \ldots \\ \text { (c) } 3 \frac{1}{2}, 3 \frac{1}{2}, 7,5,10 \frac{1}{2}, \ldots & \text { (e) } 1,5,9,13, \ldots\end{array} \)

b) \( (-3)^{2}= \)

Simplify. \( 9^{\frac{3}{2}} \)