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Find the measure of a central angle of a regular polygon with the given number of sides. Round answers to the nearest tenth of a degree, if necessary. 18 sides

Find the indicated measure. About \(650,000\) people live in a region with a 6 -mile radius. Find the population density in people per square mile.

PROBLEM SOLVINGA measuring wheel is used to calculate the length of a path. The diameter of the wheel is 8 inches. The wheel makes 87 complete revolutions along the length of the path. To the nearest foot, how long is the path? (See Example 3.)

Find the measure of a central angle of a regular polygon with the given number of sides. Round answers to the nearest tenth of a degree, if necessary. 7 sides

Find the indicated measure. About \(79,000\) people live in a circular region with a population density of about 513 people per square mile. Find the radius of the region.

ERROR ANALYSIS Describe and correct the error in finding the volume of the cylinder. \(V=2 \pi \mathrm{rh}\) \(=2 \pi(4)(3)\) \(=24 \pi\) So, the volume of the cylinder is 24\(\pi\) cubic feet.

ERROR ANALYSIS Describe and correct the error in finding the density of an object that has a mass of 24 grams and a volume of 28.3 cubic centimeters. density \(=\frac{28.3}{24} \approx 1.18\) So, the density is about 1.18 cubic centimeters per gram.

A cone has height h and a base with radiug. You want to change the cone so its volume is doubled. What is the new height if you change only the height? What is the new radius if you change only the radius? Explain.

In Exercises \(21-26,\) sketch the polyhedron. triangular prism

A pyramid has a height of 8 \(\square\)feet and a square base with a side length of 6 feet. a. How does the volume of the pyramid change when the base stays the same and the height is doubled? b. How does the volume of the pyramid change when the height stays the same and the side length of the base is doubled? c. Are your answers to parts (a) and (b) true for any square pyramid? Explain your reasoning.