Complete each sentence with the present perfect subjunctive. ¡Cuidado! The past participles used are irregular.

escribir Es excelente que tu _________ ___________________ una composicion sobre los derechos humanos.

Identify each of the following as a perfect-square trinomial, a difference of squares, a prime polynomial, or none of these.

$$4 x^2+49$$

Determine whether the statement below is true or false.

Even perfect numbers are more plentiful than Mersenne primes.

A telescope is constructed from two lenses with focal lengths of $95.0 \mathrm{~cm}$ and $15.0 \mathrm{~cm}$, the $95.0$-cm lens being used as the objective. Both the object being viewed and the final image are at infinity. (b) Find the height of the image formed by the objective of a building $60.0 \mathrm{~m}$ tall. $3.00 \mathrm{~km}$ away.

An aluminum clock pendulum having a period of $1.00 \mathrm{~s}$ keeps perfect time at $20.0^{\circ} \mathrm{C}$. (b) How much time will it gain or lose every hour?

A thin electrical heater is wrapped around the outer surface of a long cylindrical tube whose inner surface is maintained at a temperature of $5^{\circ} \mathrm{C}$. The tube wall has inner and outer radii of $25 ~\mathrm{mm}$ and $75 ~\mathrm{mm}$, respectively, and a thermal conductivity of $10 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$. The thermal contact resistance between the heater and the outer surface of the tube (per unit length of the tube) is $R_{t, c}^{\prime}=0.01 \mathrm{~m} \cdot \mathrm{K} / \mathrm{W}$. The outer surface of the heater is exposed to a fluid with $T_{\infty}=-10^{\circ} \mathrm{C}$ and a convection coefficient of $h=100 \mathrm{~W} / \mathrm{m}^{2} \cdot \mathrm{K}$. Determine the heater power per unit length of tube required to maintain the heater at $T_{o}=25^{\circ} \mathrm{C}$.

The function sum lists works only with two lists of exactly nine elements.

(a) Fix the function to work with lists of any size.

(b) Fix the function to work even if the lists are of different sizes.

(c) Rewrite the function using list comprehension. Can you reduce the function to one line yet have it still be readable?

Use algebra tiles.

b. What needs to be added to both sides of the equation to get a perfect square on the left side?

Determine whether the polynomial is a perfect-square trinomial or a difference of two squares. Then factor the polynomial.

$$x^2+10 x+25$$

Complete below sentence with the form of the verb indicated in parentheses.
Before the day in 1980 when Lake Peigneur disappeared, there __________ a salt mine under the lake for forty years. (past perfect of be)

Determine whether the following statement is true or false. Give an example or counterexample to justify your answer.

All binomials that have a perfect square in each of the two terms can be factored.

Choose the correct form of comparison for given sentence.

The hope of finding treasure draws (great, greatest) numbers of people, seeking untold riches.

Choose the letter of the word that is the closest in meaning to the first word.

cleave: (a) depart, (b) grow, (c) adhere

Rewrite the expression $y^2-x^2-8 x-41$ as a difference of two squares minus a perfect-square polynomial to show that $y^2-x^2-8 x-41=(y+5)(y-5)-(x+4)^2$