To estimate the harbor seal population in Bristol Bay, scientists radio-tagged 33 seals. Several days later, they collected a sample of 40 seals, and 24 of them were tagged. Estimate the seal population of the bay.

Jillian must average at least 90 on two quiz scores before she can move to the next skill level. Jillian got a 92 on her first quiz. What scores could Jillian get on her second quiz in order to move to the next skill level?

Simplify: $\frac{a^{-1}+b^{-1}}{\frac{a^2-b^2}{a b}}$

Recall the formula for calculating the magnitude of an earthquake, $M=\frac{2}{3} \log \left(\frac{S}{S_0}\right)$. One earthquake has magnitude $3.9$ on the MMS scale. If a second earthquake has 750 times as much energy as the first, find the magnitude of the second quake. Round to the nearest hundredth.

For the following exercises, enter the data from each table into a graphing calculator and graph the resulting scatter plots. Determine whether the data from the table could represent a function that is linear, exponential, or logarithmic.

$$\begin{array}{|c|c|c|c|c|c|c|c|c|} \hline x & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 \\ \hline f(x) & 2.4 & 2.88 & 3.456 & 4.147 & 4.977 & 5.972 & 7.166 & 8.6 & 10.32 & 12.383 \\ \hline \end{array}$$

A substance has a half-life of 2.045 minutes. If the initial amount of the substance was 132.8 grams, how many half-lives will have passed before the substance decays to 8.3 grams? What is the total time of decay?

The distance by highway between Richmond and Waterbury is 70 km, and the distance by rail is 60 km. A car and a train leave Richmond at the same time and arrive in Waterbury at the same time, the car having traveled 15 km/hr faster than the train. Find the speed of the car and the speed of the train.

Use this scenario: A tumor is injected with $0.5$ grams of Iodine-125, which has a decay rate of $1.15 \%$ per day.

The half-life of Radium-$226$ is $1590$ years. What is the annual decay rate? Express the decimal result to four significant digits and the percentage to two significant digits.

The half-life of radium-226 is 1590 years.

Find the mass that will remain after 1000 years.

Find the LCM of $8 x^5, 24 x^2$.

Simplify $\frac{6 x^2+54}{4 x^2+36}$ , if possible. Then verify by evaluating.

For the following exercise, use this scenario: A doctor prescribes 125 milligrams of a therapeutic drug that decays by about $30 \%$ each hour.
Using the model found in the previous exercise, find $f(10)$ and interpret the result. Round to the nearest hundredth.

For the following exercise,

Use this scenario: A doctor prescribes $125$ milligrams of a therapeutic drug that decays by about $30 \%$ each hour.

To the nearest hour, what is the half-life of the drug?

Use this scenario: A doctor prescribes $125$ milligrams of a therapeutic drug that decays by about $30 \%$ each hour.

Use this scenario: A doctor prescribes $125$ milligrams of a therapeutic drug that decays by about $30 \%$ each hour.

To the nearest hour, what is the half-life of the drug?