Usando las que Ud. expresiones dadas, escriba ocho frases que formarán una carta en Ia que Ud. acepta la invitación de un(a) amigo(a).

No creía _________________________

A solution of $\mathrm{NaOH}$ has a pH of $10.50$. How many grams of $\mathrm{CaO}$ should be dissolved in sufficient water to make $1.00 \mathrm{~L}$ of a solution having the same $\mathrm{pH}$ ?

Fill in the blank the term that best completes the sentence. The term___describes the difference in inherited traits that one organism has from others of the same species.

Consider the following species.

$$\mathrm{Cr}^{3+} \quad \mathrm{Hg}(l) \quad \mathrm{H}_2 \text { (acidic) } \quad \mathrm{Sn}^{2+} \quad \mathrm{Br}_2 \text { (acidic) }$$

Classify each species as oxidizing agent, reducing agent, or both. Arrange the oxidizing agents in order of increasing strength. Do the same for the reducing agents.

Use the formula $\mathrm{pH}=-\log [H+]$ to find the pH of the substance given its concentration of hydrogen ions.

milk: $[H+]=2.51 \times 10^{-7}$ mole per liter

Compare your answer in part (a) to a real soda can, which has a volume of 354 $cm^3$, a radius of 3.1 cm, and a height of 12.0 cm, to conclude the real soda cans do not seem to have an optimal design. Then use the fact that real soda cans have a double thickness in their top and bottom surfaces to find the radius and height that minimizes the surface area of a real can (the surface areas of the top and bottom are now twice their values in part (a)). Are these dimensions closer to the dimensions of a real soda can?

Choose one recreational activity that you enjoy. Describe what you already do to prevent injuries while participating in that activity. In what ways can you better protect yourself from injuries in the future?

How many years have passed since the publication of The Origin of Species? Explain why is its publication still considered so important.

What were the key differences in how European colonizers understood climate (excerpt 1) and how Native peoples in the Southwest understood climate (excerpt 2)?

delete

State a meaning of each word element, and give a medical term from this chapter that uses it or a slight variation of it.

thoraco-

Identify each perfect tense verb by underlining it and writing either present perf., past perf., or future perf. in the blank. _____ The diligent carpenter has built ten cabinets in one month.

In this exercise, tell whether the events A and B are dependent or independent. Then find $P(A$ and $B)$.

You write each of the letters of the word BRILLIANT on pieces of paper and place them in a bag. You randomly draw one letter, do not replace it, then randomly draw a second letter.

Event A: The first letter is an $\mathrm{L}$.

Event B: The second letter is a $\mathrm{T}$.

An object is propelled upward at an angle $\theta, 45^{\circ}<\theta<90^{\circ}$, to the horizontal with an initial velocity of $v_0$ feet per second from the base of a plane that makes an angle of $45^{\circ}$ with the horizontal. See the illustration. If air resistance is ignored, the distance $R$ that it travels up the inclined plane is given by

$$R=\frac{v_0^2 \sqrt{2}}{32}[\sin (2 \theta)-\cos (2 \theta)-1]$$

Graph $R, 45^{\circ} \leq \theta \leq 90^{\circ}$, and find the angle $\theta$ that maximizes the distance $R$. Also, find the maximum distance. Use $v_0=32$ feet per second. Compare the results with the answers found earlier.