Explain the process by which tooth decay occurs.

Calculate each of the following. (a) $\left[\mathrm{GF}\left(3^{6}\right): \mathrm{GF}\left(3^{3}\right)\right]$, (b) $[\mathrm{GF}(128): \mathrm{GF}(16)]$, (c) $[\mathrm{GF}(625): \mathrm{GF}(25)]$, (d) $\left[\mathrm{GF}\left(p^{12}\right): \mathrm{GF}\left(p^{2}\right)\right]$.

A. Jacques Pr'evert (1900-1977) has probably been the most popular and widely read French poet since Victoe Hugo. Pr'evert' s first book of poetry, "Paroles (Lyrics)", appeared in late 1945 just as WWII was ending. The poem you are about to read is taken from that collection. In "Familiale",Pr'evert uses simple language of everyday life to make a profound statement about war and loss. He indicates in a matter-of-fasct way what the three members of a family do:

-La m$\`e$re fait ditricot. / Elle tricote.

• Le p$\`e$re fait des affaires.
• Le fils fait la guere.

As the poem reaches uts climax, the poet's simple statemtns about the family member's lives are interrupted. The rhythm changes, and verbs ultimately disappear from the narrative. Consider, as you read the poem, how these structural changes reinforce the poet's troubling message.

B. As you read, answer the following questions.

1. What is the nature of the characters' everyday life as conveyed in the first none lines of the poem?
2. Like a play or a film, the poem builds to a climax. What is that climax? What happens afterward?

C. Now look more closely at the structure of the poem.

1. The poem uses repetition to produce an effect and to convey meaning. For example, with what repeated phrase does Prévers suggest the characters'attitude toward their daily life? When this phrase recurs the third time, it has taken on new meaning and become associated with a terrible irony. Why? Can you point out some other instances of repetition that are significated in the poem?
2. What verb is used most frequently in the poem? What effect does this produce, and what is the effect when another verb is used instead? At what point do verbs disappear altogether?
3. Poetry is often characterized by rhyme acheme. How would you describe the rhyme scheme in this poem? Wha might this type of rhyme scheme symbolize?
4. Look at the final line of the poem. How would you explain the seeming contradiction of the poet's reference to "La vie avec le cimeti$\`e$re?

D. Now discuss the following questions with your classmates.

1. Poetry is meant to be read aloud. With a partner, or with your class as a whole, practise reading "Familiale" aloud. Does this help to appreciate Prévert'sefforts to convey meaning through the form and rhythm of this poem as well as through the words themselves?
2. Work with a partner to translate the poem. How can you use the structure and rhythm of the poem in English to covey the same message Prévert is trying to convey?
3. Good literature has a timeless quaity; readers in many differents contexts can relate it to their circumstances. Do you believe Prévert's poem has this quality?

The Conservation Society bought and planted 45 cherry trees. Each tree cost $367. What was the total cost of planting the trees?

Light from a Nd: Yag laser with a wavelength of 397 nm is incident upon a hydrogen atom in the $n=2$ state at rest. What is the highest state to which hydrogen can be excited?

Add or subtract as indicated

$$\left(x^4-3 x^2+2\right)-\left(3 x^4-2 x\right)$$

$$\left(x^4-3 x^2+2\right)-\left(3 x^4-2 x\right)$$

If $10.0 \mathrm{~g}$ of an unknown compound composed of carbon, hydrogen, and nitrogen contains $17.7 \% \mathrm{~N}$ and $3.8 \times 10^{23}$ atoms of hydrogen, what is its empirical formula?

Choose the best answer to following sentence. Explain your reasoning with one or more complete sentences.
The solar nebula was 98%
(a) rock and metal.
(b) hydrogen compounds.
(c) hydrogen and helium.

You place $80$ moles of hydrogen gas in a balloon of volume $2.5 \mathrm{~m}^3$, and find the pressure to be $1.5$ times atmospheric pressure. What is the typical speed of a hydrogen molecule?

In a game of pool, ball $A$ is moving with the velocity $\mathbf{v}_0=v_0 \mathbf{i}$ when it strikes balls $B$ and $C$, which are at rest side by side. Assuming frictionless surfaces and perfectly elastic impact (i.e., conservation of energy), determine the final velocity of each ball, assuming that the path of $A$ is $(a)$ perfectly centered and that $A$ strikes $B$ and $C$ simultaneously, (b) not perfectly centered and that $A$ strikes $B$ slightly before it strikes $C$.

Use sigma notation to write the sum. $\left[1-\left(\frac{2}{n}-1\right)^{2}\right]\left(\frac{2}{n}\right)+\cdots+\left[1-\left(\frac{2 n}{n}-1\right)^{2}\right]\left(\frac{2}{n}\right)$

In a game of pool, ball $A$ is moving with a velocity $v_0$ with a magnitude of $v_0=15 \mathrm{ft} / \mathrm{s}$ when it strikes balls $B$ and $C$, which are at rest and aligned as shown. Knowing that after the collision the three balls move in the directions indicated and assuming frictionless surfaces and perfectly elastic impact (i.e., conservation of energy), determine the magnitudes of the velocities $\mathbf{v}_A, \mathbf{v}_B$, and $\mathbf{v}_C$.

Simplify. $m^{4}\left(\left(\left(m^{2}\right)^{3}\right)^{4} \right)^{2}$

Some of your friends are thinking of going to Playa del Carmen, a popular beach in Mexico. They would like more information about the place: how to get there, is it close to Cancún, a name of a fantastic hotel, what is in Xcaret, etc. Prepare a list of six to eight questions in Spanish to ask a local Mexican travel agency. If you would like, search the Internet for the answers to your questions.