Determine the oxidation number of each atom in the following compounds: sodium chloride and iron(ll) oxide .

A laundromat has 5 washing machines. A typical machine breaks down once every 5 days. A repairer can repair a machine in an average of 2.5 days. Currently, three repairers are on duty. The owner of the laundromat has the option of replacing them with a superworker, who can repair a machine in an average of $\frac{5}{6}$ day. The salary of the superworker equals the pay of the three regular employees. Breakdown and service times are exponential. Should the laundromat replace the three repairers with the superworker?

Ballplayers have been signing ever larger contracts. The highest salaries (in millions of dollars per season) for some notable players are given in the following table.

$$\begin{array}{|l|c|c|} \hline \text { Player } & \text { Year } & \text { Salary (million \$) } \\ \hline \text { Nolan Ryan } & 1980 & \ \ 1.0 \\ \text { George Foster } & 1982 & \ \ 2.0 \\ \text { Kirby Puckett } & 1990 & \ \ 3.0 \\ \text { Jose Canseco } & 1990 & \ \ 4.7 \\ \text { Roger Clemens } & 1991 & \ \ 5.3 \\ \text { Ken Griffey, Jr } & 1996 & \ \ 8.5 \\ \text { Albert Belle } & 1997 & 11.0 \\ \text { Pedro Martinez } & 1998 & 12.5 \\ \text { Mike Piazza } & 1999 & 12.5 \\ \text { Mo Vaughn } & 1999 & 13.3 \\ \text { Kevin Brown } & 1999 & 15.0 \\ \text { Carlos Delgado } & 2001 & 17.0 \\ \text { Alex Rodriguez } & 2001 & 22.0 \\ \text { Manny Ramirez } & 2004 & 22.5 \\ \text { Alex Rodriguez } & 2005 & 26.0 \\ \hline \end{array}$$

a. Examine a scatterplot of the data. Does it look straight?

b. Find the linear model for Salary vs. Year (use year since 1980) and plot the residuals. Do they look straight?

c. What model would you use for the trend in salaries?

Starting with the compounds chloromethane, chloroethane, sodium azide, sodium cyanide, and a reducing agent, suggest how the following compounds could be synthesized.
(d) tetramethylammonium chloride

If all else is the same, for which surface would the radiation pressure from light be the greatest? $(a)$ A black surface. $(b)$ A gray surface. $(c)$ A yellow surface. $(d)$ A white surface. $(e)$ All experience the same radiation pressure, because they are exposed to the same light.

On October 31, 2018, Alternative Landscapes discarded equipment that had a cost of $26,920. Accumulated Depreciation as of December 31, 2017, was$25,000. Assume annual depreciation on the equipment is $1,920. Journalize the partial-year depreciation expense and disposal of the equipment.

John Smith mistakenly expensed the cost of a long-term tangible fixed asset. Specifically, he charged the cost of a truck to a delivery expense account. How will this error affect the income statement and the balance sheet in the year in which the mistake is made?

A surface has an absorptivity of $\alpha_{\mathrm{s}}=0.72$ for solar radiation and an emissivity of $\varepsilon=0.6$ at room temperature. The surface temperature is observed to be 350 K when the direct and the diffuse components of solar radiation are $G_D =350$ and $G_d =400 W/m^2,$ respectively, and the direct radiation makes a $3,0^\circ$ angle with the normal of the surface. Taking the effective sky temperature to be 280 K, determine the net rate of radiation heat transfer to the surface at that time.

Assign oxidation states to all of the atoms of the following:

b. $\mathrm{NaH}_2 \mathrm{PO}_4$

Why do gymnasts use floor mats that are very thick?

Compare these table linens: tablecloths, runners, and place mats.

A surface is exposed to solar radiation. The direct and diffuse components of solar radiation are 350 and $250 W/m^2,$ and the direct radiation makes a $35^\circ$ angle with the normal of the surface. The solar absorptivity and the emissivity of the surface are 0.24 and 0.41, respectively. If the surface is observed to be at 315 K and the effective sky temperature is 256 K, the net rate of radiation heat transfer to the surface is (a) $−129 W/m^2$ (b) $−44 W/m^2$ (c) $0 W/m^2$ (d) $129 W/m^2$ (e) $537 W/m^2$

A sinkhole is evidence of (a) wind erosion. (b) groundwater erosion. $(c)$ ocean wave erosion. (d) stream erosion.

Why is radiation usually treated as a surface phenomenon?