The distribution of farm families (as a percent of the population) in a SO-county survey is given in the table.

$$\begin{array}{cc} \hline \text { Percent } & \begin{array}{c} \text { Number of } \\ \text { Counties } \end{array} \\ \hline 10-19 & 5 \\ 20-29 & 16 \\ 30-39 & 25 \\ 40-49 & 3 \\ 50-59 & 1 \\ \hline \end{array}$$

By using above data solve below statement Determine the standard deviation of the percent of farm families in these $50$ counties.

Use a graphing calculator to find the solutions of each equation. Round solutions to the nearest hundredth.

$$1.23 x^2+4.63 x=0$$

Find the gradient vector at each point at which it exists for the scalar fields defined by the following equations: (a) $f(x, y)=x^{2}+y^{2} \sin (x y)$, (b) $f(x, y)=e^{x} \cos y$, (c) $f(x, y, z)=x^{2} y^{3} z^{4}$, (d) $f(x, y, z)=x^{2}-y^{2}+2 z^{2}$, (e) $f(x, y, z)=\log \left(x^{2}+2 y^{2}-3 z^{2}\right)$, (f) $f(x, y, z)=x^{y^{z}}$.

Solve the equation check your solution. $10 x+2=32$

The chart shows the amount of oxygen and carbon dioxide exchanged through the skin and lungs of a frog for a period of one year.

The lowest rate of gas exchange is most likely the result of

(1) increased mating activity

(2) elevated body temperature

(3) environmental conditions

(4) competition with other species

For the titration of $50.0 \mathrm{~mL}$ of $0.150 \mathrm{M}$ ethylamine, $\mathrm{C}_2 \mathrm{H}_5 \mathrm{NH}_2$, with $0.100 \mathrm{MHCl}$, find the $\mathrm{pH}$ at each of the following points, and then use that information to sketch the titration curve and decide on an appropriate indicator.
At the beginning, before $\mathrm{HCl}$ is added

Use a calculator to find each root or power: Give as many digits as your display shows.

$$\sqrt[6]{\pi^{-1}}$$

Find an equation that has the given numbers as solutions. For example, 3 and -2 are solutions to $x^2 - x - 6 = 0$.

$$2, 2$$

Translate the phrase into an algebraic expression. eight more than the amount Kira saved

Decrease the following by the given percentage:

a 120 by 25%

b 40 by 5%

c 90 by 90%

d 1000 by 10%

e 80 by 37.5%

f 75 by 42%

By completing the square, solve each equation. Give (a) exact solutions and (b) solutions rounded to the nearest thousandth.

$$(x-3)(x+1)=1$$

If $a$ is a constant, rewrite the equation $x^3-a x^2+a^2 x-$ $a^3=0$ in a form that clearly shows its solutions. What are the solutions?

Solve each equation by factoring or by using the quadratic formula. If the solutions involve square roots, give both the exact solutions and the approximate solutions to three decimal places. $k^{2}-10 k=-20$

Solve each equation by factoring or by using the quadratic formula. If the solutions involve square roots, give both the exact solutions and the approximate solutions to three decimal places. $3 x^{2}-5 x+1=0$