The mean of 5 numbers is 4 . What happens to the mean if the number 13 is added to the data set? (A) The mean increases by 9 . (B) The mean does not change. O) The mean decreases by 1.5 . OD) The mean increases by 1.5 .

2. Determina el dominio y el rango de las siguientes funciones con algunas restricciones. a) \( f(x)=\frac{x}{x+0} \) b) \( g(x)=\frac{3 x-2}{x-1} \) c) \( f(x)=\frac{x}{x+12} \) d) \( g(x)=\frac{2 x+3}{x-4} \)

(7) Em uma perquisa, \( 80 \% \) dar alunor preferen matematreare as \( 50 \% \) alunor, quantar preferem matematuca.

3. By using the intermediate value theorem, the two curves \( \frac{f(x)=x^{4}-x^{2}+4 x \text { and }}{16-4+8} \) \( g(x)=x+1 \) intersect in the interval \( \begin{array}{ll}\text { (a) }(2,3) & 2=3,20 \quad 3=4 \\ \text { (b) }(1,2) \\ \text { (c) }(0,1) \\ \text { (d) }(1,3) \\ \text { (e) }(-1,0) & 1=2,4\end{array} \)

43 Soient les nombres complexes \( z_{1}=\frac{4-\mathrm{i}}{3+2 \mathrm{i}} \) et \( z_{2}=\frac{4+\mathrm{i}}{3-2 \mathrm{i}} \). 1. Vérifier que \( z_{1}+z_{2} \) est un nombre réel. 2. Que peut-on en déduire pour les parties imaginaires de \( z_{1} \) et \( z_{2} \) ? 3. Vérifier que \( z_{1}-z_{2} \) est un nombre imaginaire pur. 4. Que peut-on en déduire pour les parties réelles de \( z_{1} \) et \( z_{2} \) ?

What was a negative consequence of the Industrial Revolution? A. Stock market instability B. Overcrowding of cities C. Poor quality crops D. Lack of needed workers