a
100 cm²
b
9 cm²
c
225 cm²
d
28.26 cm²
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Answer:
28.26 cm^2
Step-by-step explanation:
A = (pi)r^2
A = 3.14 * (3 cm)^2
A = 3.14 * 9 cm^2
A = 28.26 cm^2