find the area and circumference.
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Answer:
Step-by-step explanation:
The radius is half the diameter, so is ...
r = d/2 = 15 cm/2 = 7.5 cm
The area formula is ...
A = πr²
Filling in the radius, we have ...
A = π·(7.5 cm)² = 56.25π cm² ≈ 176.7 cm² . . . area
__
The circumference formula is ...
C = πd
Filling in the diameter, we have ...
C = π·(15 cm) = 15π cm ≈ 47.1 cm . . . circumference