91Ó°ÊÓ

Use a vertical motion model to find how long it will take for the object to reach the ground. Round your solution to the nearest tenth. A lacrosse player throws a ball upward from her playing stick from an initial height of 7 feet, with an initial velocity of 90 feet per second.

Use the following information. A tsunami is a destructive, fast-moving ocean wave that is caused by an undersea earthquake, landslide, or volcano. Scientists can predict arrival times of tsunamis by using water depth to calculate the speed of a tsunami. A model for the speed \(s\) (in meters per second) at which a tsunami moves is \(s=\sqrt{g d}\) where \(d\) is the depth (in meters) and \(g\) is 9.8 meters per second per second. CRITICAL THINKING Is the speed of a tsunami in water that is 4000 meters deep four times the speed of a tsunami in water that is 1000 meters? Explain why or why not.

Use a calculator to evaluate the expression. Round the results to the nearest hundredth. $$ \frac{5 \pm 6 \sqrt{3}}{3} $$

Write the number in scientific notation. (Lesson 8.5) $$ 0.0000008 $$

Write the number in scientific notation. (Lesson 8.5) $$ 23,000 $$

MULTIPLE CHOICE Which step would you use to rationalize the denominator of \(\frac{\sqrt{3}}{\sqrt{10}} ?\) (F) Multiply by \(\frac{\sqrt{10}}{\sqrt{10}}\) (G) Multiply by \(\frac{\sqrt{10}}{\sqrt{3}}\) (H) Multiply by \(\sqrt{10}\) (J) Multiply by 10.

Solve the inequality. Then graph the solution. (Lesson 6.2) $$-3 x \geq 15$$

Divide. Write the answer as a fraction or as a mixed number in simplest form. $$ \frac{4}{5} \div 10 $$

Write the fraction as a terminating or repeating decimal. $$ \frac{8}{9} $$

Divide. Write the answer as a fraction or as a mixed number in simplest form. $$ \frac{2}{3} \div 63 $$