Assume that A is a matrix with three rows. Find the elementary matrix E such that E A gives the matrix resulting from A after the given row operation is performed. $R_{3} \Leftrightarrow R_{2}$

Solve each proportion. $\frac{3}{20}=\frac{n}{100}$

Assume that A is a matrix with three rows. Find the matrix B such that B A gives the matrix resulting from A after the given row operations are performed.

$$\begin{aligned} -2 R_{1}+R_{2} & \Rightarrow R_{2} \\ 5 R_{3} & \Rightarrow R_{3} \end{aligned}$$

The detergent-like substance that keeps the alveoli from collapsing between breaths because it reduces the surface tension of the water film in the alveoli is called (a) lecithin, (b) bile, (c) surfactant, (d) reluctant..

Under ordinary circumstances, the inflation reflex is initiated by (a) the inspiratory center, (b) the ventral respiratory group, (c) overinflation of the alveoli and bronchioles, (d) the pontine respiratory centers.

Cutting the phrenic nerves will result in (a) air entering the pleural cavity, (b) paralysis of the diaphragm, (c) stimulation of the diaphragmatic reflex, (d) paralysis of the epiglottis.

Expand each of the given matrix expressions and combine as many terms as possible. Assume that all matrices are $n \times n$. $(A+I)(A-I)$

Find A, x, and b such that Ax = b corresponds to the given linear system.

$$\begin{array}{l} 2 x_{1}+8 x_{2}-4 x_{3}=-10 \\ -x_{1}-3 x_{2}+5 x_{3}=4 \end{array}$$

Assume that A is a matrix with three rows. Find the matrix B such that BA gives the matrix resulting from A after the given row operations are performed.

$$\begin{array}{c} -3 R_{1}+R_{2} \rightarrow R_{2} ,\\ 2 R_{1}+R_{3} \rightarrow R_{3} ,\\ -R_{2}+R_{3} \rightarrow R_{3} \end{array}$$

Marta is cutting a 16-inch and a 28-inch submarine sandwich for a party. How long is the longest possible piece if she cuts them all to be the same length?

Predict the major products of the following reactions, including stereochemistry where appropriate. (a) 2.2.-dimethyloxirane $+\mathrm{H}^{+} / \mathrm{H}_{2}^{18} \mathrm{O}$ (oxygen-labeled water). (b) 2.2-dimethyloxirane+$\mathrm{H}^{18} \mathrm{O}^{-} / \mathrm{H}_{2}^{18} \mathrm{O}$. (c) (2S,3R)-2-ethyl-2,3-dimethyloxirane$+\mathrm{CH}_{3} \mathrm{O}^{-} / \mathrm{CH}_{3} \mathrm{OH}$. (e) (2S,3R)-2-ethyl-2,3-dimethyloxirane$+\mathrm{H}^{+} / \mathrm{CH}_{3} \mathrm{OH}$

Harry, the swimmer with the fastest time on the Springfield College swim team, routinely hyperventilates before a meet, as he says, "to sock some more oxygen into my lungs so I can swim longer without having to breathe." First of all, what basic fact about oxygen loading has Harry forgotten (a lapse leading to false thinking)? Second, how is Harry jeopardizing not only his time but his life?

Solve the inequality, and write the solution set in interval notation if possible.

$$15<|-2 d-3|+6$$

The measures of the angles of a triangle are in the ratio 1:3:6. What are the measures of the angles?