Underline the appositive in the following sentence. Then, circle the word or words it describes or identifies.

The word palindrome comes from Greek and means “running back again.”

Solve each problem involving an angle of elevation or depression. the example in this section.

The shadow of a vertical tower is $40.6 \mathrm{~~m}$ long when the angle of elevation of the sun is $34.6^{\circ}$. Find the height of the tower.

How do we know that white light is composed of a rainbow of colors?

Solve the absolute value inequality. Write solutions in interval notation. Check solutions by back substitution, or using a calculator. $-2|w|-5 \leq-11$

Construct the domino family $\mathcal{A}$ of subsets of the black squares associated with the white squares of the board B in figure earlier. (Consider the square in the upper left corner to be white.) Determine a tiling of this board and the associated SDR of $\mathcal{A}$.

Tell whether the following statements are always, sometimes, or never true. If a statement is not always true, explain. The product of a non-zero rational number and an irrational number is irrational.

For the following exercises, write the linear system from the augmented matrix.

$$\left[\begin{array}{lll|l} 1 & 2 & 3 & 4 \\ 0 & 5 & 6 & 7 \\ 0 & 0 & 8 & 9 \end{array}\right]$$

This augmented matrix is in row echelon form and represents a linear system. Use back-substitution to solve the system if possible.

$$\left[\begin{array}{rr|r}1 & -1 & 2 \\ 0 & 1 & 0\end{array}\right]$$

Without referring back to the text. Fill in the blank or answer true/false. The vectors $\langle- 4,-6,10\rangle$ and $\langle- 10,-15,25\rangle$ are parallel. _____

A train is heading due west from St. Louis. At noon, at plane flying horizontally due north at a fixed altitude of $4$ miles passes directly over the train. When the train has traveled another mile, it is going $80 \mathrm{mph}$, and the plane has traveled another $5$ miles and is going $500 \mathrm{mph}$. At that moment, how fast is the distance between the train and the plane increasing?

Write the system of linear equations that is represented by the given augmented matrix. Assume that the variables are $x_{1}$ and $x_{2}$.

$$\left[\begin{array}{rr|r}{1} & {-2} & {12} \\ {0} & {1} & {6}\end{array}\right]$$

Solve the absolute value inequality. Write solutions in interval notation. Check solutions by back substitution, or using a calculator. $3|p+4|+5<8$

Write an expression that you can use to represent the output quantity in terms of the input quantity. Enter this expression in the "Expression" row under output.

Find an equivalent equation in rectangular coordinates.

$$r=2$$