Answer:
a. area = 1.745 cm²
b. mass = 319 mg
Explanation:
a. The area of a sector is given by ...
A = (1/2)r²θ . . . . . where r is the radius, and θ is the central angle in radians
The area of one of these sectors is ...
A = (1/2)(2 cm)²(50π/180) ≈ 1.745 cm²
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b. The mass of the sector is proportional to the central angle. When the angle is 360°, all of the mass is included. Here, each sector is only 50°, so the proportion is 50/360 of the mass, or ...
mass = (2.3 g)(50/360) = 0.3194444... g ≈ 319 mg