91Ó°ÊÓ

In Exercises \(10-13,\) find the approximate circumference and area of each circle with the given radius or diameter using the calculator to approximate the answer to the nearest hundredth. \(d=12.00 \mathrm{mi}\)

In a regular octagon, the measure of each apothem is 5.76 centimeters and each side is \(6 \mathrm{cm}\). Find the area.

The area of a sector of a circle is \(24 \pi\) yd \(^{2}\). If the arc of the sector is \(60^{\circ}\), find the diameter of the circle.

In Exercises \(10-13,\) find the approximate circumference and area of each circle with the given radius or diameter using the calculator to approximate the answer to the nearest hundredth. \(d=18.36 \mathrm{yd}\)

In a regular octagon, the measure of each radius is 29 in. and each apothem is 21 in. Find the area.

How much more cross-sectional area is there for water to pass through in a \(\frac{3}{4}\) -inch-diameter water hose than there is in a \(\frac{1}{2}\) -inch-diameter water hose? Round to the nearest hundredth.

The area of a sector of a circle is \(50 \pi \mathrm{cm}^{2} .\) If the arc of the sector is \(45^{\circ},\) find the diameter of the circle.

Find the area of a sector of a circle if the radius is 12.6 inches and the arc of the sector is \(25^{\circ}\). Give the answer correct to the nearest tenth of a square inch.

A circular garden has radius \(9 \mathrm{m}\). If a 1 -meter-wide circular walk surrounds it, what is the area of the walk? [Hint: Find the area of a circle with 10-meter radius and subtract the area of the garden.] Round to the nearest hundredth.

Estimate to the nearest tenth of a unit, the area of a regular 20 -gon with an apothem 8.5 centimeters.