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Answer:
The answer is 4π cm or 12.6 cm.
Step-by-step explanation:
First, you have to find the radius of circle by dividing diameter by 2 :
[tex]diameter = 4cm[/tex]
[tex]radius = 4 \div 2[/tex]
[tex]radius = 2cm[/tex]
Next you have to use circumference formula, C = 2×π×r where r represents radius of circle :
[tex]c = 2 \times \pi \times r[/tex]
Let r = 2cm,
[tex]c = 2 \times \pi \times 2[/tex]
[tex]c = 4\pi cm[/tex]