1. Measuring Angles

CONCEPT PREVIEW Find the radius of each circle.

Convert each degree measure to radians. Leave answers as multiples of π. See Examples 1(a) and 1(b). ―315°

CONCEPT PREVIEW Find the area of each sector.

Find the area of the sector of a circle of radius r formed by a central angle θ. Express area in terms of π. Then round your answer to two decimal places. Radius, r: 4 inches Central Angle, θ: θ = 240°

Distance Traveled by a Minute Hand Suppose the tip of the minute hand of a clock is 3 in. from the center of the clock. For each duration, determine the distance traveled by the tip of the minute hand. Leave answers as multiples of π . 4.5 hr

CONCEPT PREVIEW Find the area of each sector.

Convert each radian measure to degrees. See Examples 2(a) and 2(b). ―8π/5

CONCEPT PREVIEW Find the measure of each central angle (in radians).

An angle measures $4.3$ radians. To the nearest degree, what is its measure in $degrees$?

CONCEPT PREVIEW Find the radius of each circle.

If arc CD is one-fourth of the circumference of a circle, what is the radian measure of the central angle subtended by arc CD?

An arc on a circle measures $250°$. Within which range is the radian measure of the central angle?

How many radians are in a full circle?

Find the length to three significant digits of each arc intercepted by a central angle in a circle of radius r. See Example 1.

r = 4.82 m , θ = 60°