1. C = 62.83

2. C = 75.40

3. C = 1,696.46

4. C = 15.71

5. C = 2.51

1.

First, get the diameter:

Diameter = Radius × 2

Diameter = (10 cm) 2

Diameter = 20 cm

Now, solve for the circumference:

C = πd

C = 3.14(20cm)

C = 62.83

2.

First, get the diameter:

Diameter = Radius × 2

Diameter = (12 cm) 2

Diameter = 24 cm

Now, solve for the circumference:

C = πd

C = 3.14(24cm)

C = 75.40

3.

First, get the diameter:

Diameter = Radius × 2

Diameter = (270 mm) 2

Diameter = 540 mm

Now, solve for the circumference:

C = πd

C = 3.14(540 mm)

C = 1,696.46

4.

First, get the diameter:

Diameter = Radius × 2

Diameter = (2.5 inches) 2

Diameter = 5 inches

Now, solve for the circumference:

C = πd

C = 3.14(5 inches)

C = 15.71

5.

First, get the diameter:

Diameter = Radius × 2

Diameter = (0.4 inches) 2

Diameter = 0.8 inches

Now, solve for the circumference:

C = πd

C = 3.14(0.8 inches)

C = 2.51