Describe a natural concept that you know fully but that would be difficult for someone else to understand and explain why it would be difficult.

Plain doughnuts from a particular bakery have an average mass of $32.6$ g, whereas jam-filled doughnuts from the same bakery have an average mass of $40.0 \mathrm{~g}$. (a) Determine the mass of a dozen plain doughnuts and the mass of a dozen jam-filled doughnuts. (b) Determine the number of doughnuts in a kilogram of plain and the number in a kilogram of jam-filled. (c) Determine the mass of plain doughnuts that contains the same number of doughnuts as a kilogram of jam-filled. (d) Determine the total mass of a dozen doughnuts consisting of three times as many plain as jam-filled.

What is the molar mass of Sodium Acetate?

A compound has the following percentage composition by mass: copper, $33.88\%$; nitrogen, $14.94\%$; oxygen, $51.18\%$. Determine the empirical formula of the compound.

Use reference angles to evaluate the expression.

If $\cos t=\frac{1}{2}$, what is the $\cos (-t)$?

Calculate the molar mass of xenon trioxide.

Use your result from the previous question to solve each of these for the unknown variable:

a. $log _{11} 11=x$

b. $log _5 p=1$

c. $log _q 3=1$

Which of the following statements describes the characteristic feature of a carrier protein in a plasma membrane?

a. It exhibits specificity for a particular type of molecule

b. It works against diffusion

c. It requires the expenditure of cellular energy to function

d. It has no hydrophobic reactions

One of the things you were asked to estimate in Lesson 1-4 was the monthly payment on a $\$ 10,000$ car if you wanted to pay it off in 3 years. If the interest rate is $3 \%$, the expression below can be used to calculate the exact monthly payment.

$$\frac{\left(\frac{0.03}{12}\right)(10,000)\left(1+\frac{0.03}{12}\right)^{36}}{\left(1+\frac{0.03}{12}\right)^{36}-1}$$

Clearly, this is a pretty complicated expression that would require some help from a calculator or computer. But you can't get that help unless you understand the order of operations, because calculators and computers are programmed to obey those rules. Spend some time writing this expression the way you'd need to enter it into a calculator or spreadsheet. Use " $\wedge$ " for exponents, " $*$ " for multiplication, and " $/$ " for division.

A turntable with a moment of inertia of $5.4 \times 10^{-3} \mathrm{~kg} \cdot \mathrm{m}^2$ rotates freely with an angular speed of $33 \frac{1}{3} \mathrm{rpm}$. Riding on the rim of the turntable, $15 \mathrm{~cm}$ from the center, is a cute, $32~\mathrm{g}$ mouse. If the mouse walks to the center of the turntable, calculate the angular speed of the turntable when the mouse reaches the center.

Use graphical methods to solve the inequality.

$$2 x^2 \leq 5 x+6$$

Predict three reasons why the immune system might not respond correctly to foreign material in the body.

In this exercise you will need to use the graph of $f(x)=x^2$ below to sketch the graph of the function $H(x)=x^2+1$.

Evaluate exactly all six trigonometric functions of the angle. Use reference triangles and not your calculator.

$$420°$$